Remove ActiveRecord QueryCache patch
The bug in http://github.com/rails/rails/issues/36587 is now fixed in https://github.com/rails/rails/pull/36618
The patch in lib/gitlab/patch/active_record_query_cache.rb
and config/initializers/active_record_query_cache.rb
will not be required once we upgrade to the next stable release (5.2.4 or 6.0.0)
Edited by Heinrich Lee Yu