Enable even more frozen string in lib/gitlab

Enables frozens string for the following:

* lib/gitlab/conflict/**/*.rb
* lib/gitlab/cross_project_access/**/*.rb
* lib/gitlab/cycle_analytics/**/*.rb
* lib/gitlab/data_builder/**/*.rb
* lib/gitlab/database/**/*.rb
* lib/gitlab/dependency_linker/**/*.rb
* lib/gitlab/diff/**/*.rb
* lib/gitlab/downtime_check/**/*.rb
* lib/gitlab/email/**/*.rb
* lib/gitlab/etag_caching/**/*.rb

Partially addresses gitlab-org/gitlab-ce#47424.

29 files changed, 58 insertions, 0 deletions

diff --git a/lib/gitlab/cycle_analytics/base_event_fetcher.rb b/lib/gitlab/cycle_analytics/base_event_fetcher.rb
index e3e3767cc75..304d60996a6 100644
--- a/lib/gitlab/cycle_analytics/base_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/base_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/base_query.rb b/lib/gitlab/cycle_analytics/base_query.rb
index 86d708be0d6..36231b187cd 100644
--- a/lib/gitlab/cycle_analytics/base_query.rb
+++ b/lib/gitlab/cycle_analytics/base_query.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module BaseQuery
diff --git a/lib/gitlab/cycle_analytics/base_stage.rb b/lib/gitlab/cycle_analytics/base_stage.rb
index 038d5a19bc4..e2d6a301734 100644
--- a/lib/gitlab/cycle_analytics/base_stage.rb
+++ b/lib/gitlab/cycle_analytics/base_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class BaseStage
diff --git a/lib/gitlab/cycle_analytics/code_event_fetcher.rb b/lib/gitlab/cycle_analytics/code_event_fetcher.rb
index 06357c9b377..591db3c35e6 100644
--- a/lib/gitlab/cycle_analytics/code_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/code_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class CodeEventFetcher < BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/code_stage.rb b/lib/gitlab/cycle_analytics/code_stage.rb
index 5f9dc9a4303..2e5f9ef5a40 100644
--- a/lib/gitlab/cycle_analytics/code_stage.rb
+++ b/lib/gitlab/cycle_analytics/code_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class CodeStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/event_fetcher.rb b/lib/gitlab/cycle_analytics/event_fetcher.rb
index 50e126cf00b..98a30a8fc97 100644
--- a/lib/gitlab/cycle_analytics/event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module EventFetcher
diff --git a/lib/gitlab/cycle_analytics/issue_event_fetcher.rb b/lib/gitlab/cycle_analytics/issue_event_fetcher.rb
index 1754f91dccb..30c6ead8968 100644
--- a/lib/gitlab/cycle_analytics/issue_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/issue_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class IssueEventFetcher < BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/issue_stage.rb b/lib/gitlab/cycle_analytics/issue_stage.rb
index 7b03811efb2..4eae2da512c 100644
--- a/lib/gitlab/cycle_analytics/issue_stage.rb
+++ b/lib/gitlab/cycle_analytics/issue_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class IssueStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/metrics_tables.rb b/lib/gitlab/cycle_analytics/metrics_tables.rb
index f5d08c0b658..3e0302d308d 100644
--- a/lib/gitlab/cycle_analytics/metrics_tables.rb
+++ b/lib/gitlab/cycle_analytics/metrics_tables.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module MetricsTables
diff --git a/lib/gitlab/cycle_analytics/permissions.rb b/lib/gitlab/cycle_analytics/permissions.rb
index 1e11e84a9cb..afefd09b614 100644
--- a/lib/gitlab/cycle_analytics/permissions.rb
+++ b/lib/gitlab/cycle_analytics/permissions.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class Permissions
diff --git a/lib/gitlab/cycle_analytics/plan_event_fetcher.rb b/lib/gitlab/cycle_analytics/plan_event_fetcher.rb
index 086203b9ccc..db8ac3becea 100644
--- a/lib/gitlab/cycle_analytics/plan_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/plan_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class PlanEventFetcher < BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/plan_stage.rb b/lib/gitlab/cycle_analytics/plan_stage.rb
index 1a0afb56b4f..513e4575be0 100644
--- a/lib/gitlab/cycle_analytics/plan_stage.rb
+++ b/lib/gitlab/cycle_analytics/plan_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class PlanStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/production_event_fetcher.rb b/lib/gitlab/cycle_analytics/production_event_fetcher.rb
index 0fa2e87f673..6681cb42c90 100644
--- a/lib/gitlab/cycle_analytics/production_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/production_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class ProductionEventFetcher < IssueEventFetcher
diff --git a/lib/gitlab/cycle_analytics/production_helper.rb b/lib/gitlab/cycle_analytics/production_helper.rb
index d0ca62e46e4..aff65b150fb 100644
--- a/lib/gitlab/cycle_analytics/production_helper.rb
+++ b/lib/gitlab/cycle_analytics/production_helper.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module ProductionHelper
diff --git a/lib/gitlab/cycle_analytics/production_stage.rb b/lib/gitlab/cycle_analytics/production_stage.rb
index 0fa8a65cb99..6fd7214dce7 100644
--- a/lib/gitlab/cycle_analytics/production_stage.rb
+++ b/lib/gitlab/cycle_analytics/production_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class ProductionStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/review_event_fetcher.rb b/lib/gitlab/cycle_analytics/review_event_fetcher.rb
index dada819a2a8..de100295281 100644
--- a/lib/gitlab/cycle_analytics/review_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/review_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class ReviewEventFetcher < BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/review_stage.rb b/lib/gitlab/cycle_analytics/review_stage.rb
index cfbbdc43fd9..294b656bc55 100644
--- a/lib/gitlab/cycle_analytics/review_stage.rb
+++ b/lib/gitlab/cycle_analytics/review_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class ReviewStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/stage.rb b/lib/gitlab/cycle_analytics/stage.rb
index 28e0455df59..1bd40a7aa18 100644
--- a/lib/gitlab/cycle_analytics/stage.rb
+++ b/lib/gitlab/cycle_analytics/stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module Stage
diff --git a/lib/gitlab/cycle_analytics/stage_summary.rb b/lib/gitlab/cycle_analytics/stage_summary.rb
index fc77bd86097..5198dd5b4eb 100644
--- a/lib/gitlab/cycle_analytics/stage_summary.rb
+++ b/lib/gitlab/cycle_analytics/stage_summary.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class StageSummary
diff --git a/lib/gitlab/cycle_analytics/staging_event_fetcher.rb b/lib/gitlab/cycle_analytics/staging_event_fetcher.rb
index 2f014153ca5..70ce82383b3 100644
--- a/lib/gitlab/cycle_analytics/staging_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/staging_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class StagingEventFetcher < BaseEventFetcher
diff --git a/lib/gitlab/cycle_analytics/staging_stage.rb b/lib/gitlab/cycle_analytics/staging_stage.rb
index d5684bb9201..dbc2414ff66 100644
--- a/lib/gitlab/cycle_analytics/staging_stage.rb
+++ b/lib/gitlab/cycle_analytics/staging_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class StagingStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/summary/base.rb b/lib/gitlab/cycle_analytics/summary/base.rb
index a917ddccac7..709221c648e 100644
--- a/lib/gitlab/cycle_analytics/summary/base.rb
+++ b/lib/gitlab/cycle_analytics/summary/base.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module Summary
diff --git a/lib/gitlab/cycle_analytics/summary/commit.rb b/lib/gitlab/cycle_analytics/summary/commit.rb
index 550c1755a71..f0019b26fa2 100644
--- a/lib/gitlab/cycle_analytics/summary/commit.rb
+++ b/lib/gitlab/cycle_analytics/summary/commit.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module Summary
diff --git a/lib/gitlab/cycle_analytics/summary/deploy.rb b/lib/gitlab/cycle_analytics/summary/deploy.rb
index 099d798aac6..3b56dc2a7bc 100644
--- a/lib/gitlab/cycle_analytics/summary/deploy.rb
+++ b/lib/gitlab/cycle_analytics/summary/deploy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module Summary
diff --git a/lib/gitlab/cycle_analytics/summary/issue.rb b/lib/gitlab/cycle_analytics/summary/issue.rb
index 9bbf7a2685f..51695c86192 100644
--- a/lib/gitlab/cycle_analytics/summary/issue.rb
+++ b/lib/gitlab/cycle_analytics/summary/issue.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     module Summary
diff --git a/lib/gitlab/cycle_analytics/test_event_fetcher.rb b/lib/gitlab/cycle_analytics/test_event_fetcher.rb
index a2589c6601a..4d5ea5b7c34 100644
--- a/lib/gitlab/cycle_analytics/test_event_fetcher.rb
+++ b/lib/gitlab/cycle_analytics/test_event_fetcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class TestEventFetcher < StagingEventFetcher
diff --git a/lib/gitlab/cycle_analytics/test_stage.rb b/lib/gitlab/cycle_analytics/test_stage.rb
index 0e9d235ca79..c31b664148b 100644
--- a/lib/gitlab/cycle_analytics/test_stage.rb
+++ b/lib/gitlab/cycle_analytics/test_stage.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class TestStage < BaseStage
diff --git a/lib/gitlab/cycle_analytics/updater.rb b/lib/gitlab/cycle_analytics/updater.rb
index 953268ebd46..c642809a792 100644
--- a/lib/gitlab/cycle_analytics/updater.rb
+++ b/lib/gitlab/cycle_analytics/updater.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class Updater
diff --git a/lib/gitlab/cycle_analytics/usage_data.rb b/lib/gitlab/cycle_analytics/usage_data.rb
index 5122e3417ca..913ee373f54 100644
--- a/lib/gitlab/cycle_analytics/usage_data.rb
+++ b/lib/gitlab/cycle_analytics/usage_data.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module CycleAnalytics
     class UsageData