Merge branch 'depracated-migration-inheritance' into 'master'

ActiveRecord::Migration -> ActiveRecord::Migration[5.0] for AddIndexesToCiBuildsAndPipelines

See merge request gitlab-org/gitlab-ce!24167

changelogs/unreleased/deprecated-migration-inheritance-2.yml

+---
+title: ActiveRecord::Migration -> ActiveRecord::Migration[5.0] for AddIndexesToCiBuildsAndPipelines
+merge_request: 24167
+author: Jasper Maes
+type: other

db/migrate/20181119132520_add_indexes_to_ci_builds_and_pipelines.rb

 # frozen_string_literal: true
 
-class AddIndexesToCiBuildsAndPipelines < ActiveRecord::Migration
+class AddIndexesToCiBuildsAndPipelines < ActiveRecord::Migration[5.0]
   include Gitlab::Database::MigrationHelpers
 
   DOWNTIME = false