Merge branch 'ab/migration-template' into 'master'

Use migration class for create table template

See merge request gitlab-org/gitlab!70491

generator_templates/active_record/migration/create_table_migration.rb

@@ -3,9 +3,7 @@
 # See https://docs.gitlab.com/ee/development/migration_style_guide.html
 # for more information on how to write migrations for GitLab.
 
-class <%= migration_class_name %> < ActiveRecord::Migration[<%= ActiveRecord::Migration.current_version %>]
-  include Gitlab::Database::MigrationHelpers
-
+class <%= migration_class_name %> < Gitlab::Database::Migration[<%= Gitlab::Database::Migration.current_version %>]
   # When using the methods "add_concurrent_index" or "remove_concurrent_index"
   # you must disable the use of transactions
   # as these methods can not run in an existing transaction.