Merge branch 'enable-scss-lint-single-line-per-selector' into 'master'

Enable SingleLinePerSelector in scss-lint

## What does this MR do?
Enables `SingleLinePerSelector` in `.scss-lint.yml`

## Are there points in the code the reviewer needs to double check?
This MR touches a lot of files, just need another pair of eyes to look through and make sure I didn't break anything.

## Why was this MR needed?
Improve SCSS maintainability and consistency

## Screenshots (if relevant)
None

## Does this MR meet the acceptance criteria?

- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
#23485

See merge request !7081

1 files changed, 6 insertions, 3 deletions

diff --git a/app/assets/stylesheets/pages/login.scss b/app/assets/stylesheets/pages/login.scss
index 2be9453aaee..3d2b024fe5c 100644
--- a/app/assets/stylesheets/pages/login.scss
+++ b/app/assets/stylesheets/pages/login.scss
@@ -41,7 +41,8 @@
     font-size: 13px;
   }
 
-  .login-box, .omniauth-container {
+  .login-box,
+  .omniauth-container {
     box-shadow: 0 0 0 1px $border-color;
     border-bottom-right-radius: 2px;
     border-bottom-left-radius: 2px;
@@ -198,7 +199,8 @@
 
 
   .form-control {
-    &:active, &:focus {
+    &:active,
+    &:focus {
       background-color: #fff;
     }
   }
@@ -261,7 +263,8 @@
     position: relative;
   }
 
-  .footer-container, hr.footer-fixed {
+  .footer-container,
+  hr.footer-fixed {
     position: absolute;
     bottom: 0;
     left: 0;