Remove unnecessary disable comments for rubocop

ee/db/post_migrate/20180417102933_drop_repository_storage_events_for_geo_events.rb

@@ -29,7 +29,6 @@ class DropRepositoryStorageEventsForGeoEvents < ActiveRecord::Migration[4.2]
   private
 
   def update_repository_storage_path(table)
-    # rubocop:disable Migration/UpdateColumnInBatches
     update_column_in_batches(table, :repository_storage_path, update_statement) do |t, q|
       q.where(t[:repository_storage_path].eq(nil))
     end

ee/db/post_migrate/20181220165848_update_package_type.rb

 # frozen_string_literal: true
-# rubocop:disable Migration/UpdateColumnInBatches
 class UpdatePackageType < ActiveRecord::Migration[5.0]
   include Gitlab::Database::MigrationHelpers