Mark services table "to be renamed"

In the next milestone this table will be renamed as per our rename table
guidelines.

lib/gitlab/database.rb

@@ -9,7 +9,8 @@ module Gitlab
     #   'old_name' => 'new_name'
     # }.freeze
     TABLES_TO_BE_RENAMED = {
-      'analytics_instance_statistics_measurements' => 'analytics_usage_trends_measurements'
+      'analytics_instance_statistics_measurements' => 'analytics_usage_trends_measurements',
+      'services' => 'integrations'
     }.freeze
 
     # Minimum PostgreSQL version requirement per documentation: