Change `be_success` to `be_successful` in specsfix-deprecation-warnings-change-success-to-successful

Fixes deprecation warning:

```
DEPRECATION WARNING: The success? predicate is deprecated and
will be removed in Rails 6.0.
Please use successful? as provided by Rack::Response::Helpers.
```

1 files changed, 4 insertions, 4 deletions

diff --git a/spec/controllers/projects/merge_requests_controller_spec.rb b/spec/controllers/projects/merge_requests_controller_spec.rb
index b1dc6a65dd4..11b1eaf11b7 100644
--- a/spec/controllers/projects/merge_requests_controller_spec.rb
+++ b/spec/controllers/projects/merge_requests_controller_spec.rb
@@ -57,7 +57,7 @@ describe Projects::MergeRequestsController do
 
           go(format: :html)
 
-          expect(response).to be_success
+          expect(response).to be_successful
         end
       end
 
@@ -66,7 +66,7 @@ describe Projects::MergeRequestsController do
 
         go(format: :html)
 
-        expect(response).to be_success
+        expect(response).to be_successful
       end
 
       context "that is invalid" do
@@ -75,7 +75,7 @@ describe Projects::MergeRequestsController do
         it "renders merge request page" do
           go(format: :html)
 
-          expect(response).to be_success
+          expect(response).to be_successful
         end
       end
     end
@@ -124,7 +124,7 @@ describe Projects::MergeRequestsController do
         it "renders merge request page" do
           go(format: :json)
 
-          expect(response).to be_success
+          expect(response).to be_successful
         end
       end
     end