Merge branch 'remove-magic-comments' into 'master'

Remove magic comments from Ruby files

## What does this MR do?

Remove magic comments (`# encoding: UTF-8`) from Ruby files.

## Why was this MR needed?

Since Ruby 2, UTF-8 is the default encoding and those comments are no longer necessary.

## What are the relevant issue numbers?

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5163#note_13134307

cc @rymai 

See merge request !5456

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 
 v 8.11.0 (unreleased)
+  - Remove magic comments (`# encoding: UTF-8`) from Ruby files !5456 (winniehell)
   - Fix of 'Commits being passed to custom hooks are already reachable when using the UI'
   - Limit git rev-list output count to one in forced push check
   - Retrieve rendered HTML from cache in one request

app/helpers/commits_helper.rb

-# encoding: utf-8
 module CommitsHelper
   # Returns a link to the commit author. If the author has a matching user and
   # is a member of the current @project it will link to the team member page.

app/uploaders/artifact_uploader.rb

-# encoding: utf-8
 class ArtifactUploader < CarrierWave::Uploader::Base
   storage :file
 

app/uploaders/attachment_uploader.rb

-# encoding: utf-8
-
 class AttachmentUploader < CarrierWave::Uploader::Base
   include UploaderHelper
 

app/uploaders/avatar_uploader.rb

-# encoding: utf-8
-
 class AvatarUploader < CarrierWave::Uploader::Base
   include UploaderHelper
 

app/uploaders/file_uploader.rb

-# encoding: utf-8
 class FileUploader < CarrierWave::Uploader::Base
   include UploaderHelper
   MARKDOWN_PATTERN = %r{\!?\[.*?\]\(/uploads/(?<secret>[0-9a-f]{32})/(?<file>.*?)\)}

app/uploaders/lfs_object_uploader.rb

-# encoding: utf-8
-
 class LfsObjectUploader < CarrierWave::Uploader::Base
   storage :file
 

spec/lib/banzai/filter/relative_link_filter_spec.rb

-# encoding: UTF-8
-
 require 'spec_helper'
 
 describe Banzai::Filter::RelativeLinkFilter, lib: true do

spec/lib/banzai/filter/table_of_contents_filter_spec.rb

-# encoding: UTF-8
-
 require 'spec_helper'
 
 describe Banzai::Filter::TableOfContentsFilter, lib: true do

spec/lib/banzai/filter/upload_link_filter_spec.rb

-# encoding: UTF-8
-
 require 'spec_helper'
 
 describe Banzai::Filter::UploadLinkFilter, lib: true do