added todo

.gitlab-ci.yml

@@ -32,6 +32,7 @@ include:
   # As long as you include this, any future includes added by the Drupal Association will be accessible to your pipelines automatically.
   # View these include files at https://git.drupalcode.org/project/gitlab_templates/
   ################
+  # @todo Remove when https://www.drupal.org/i/3421674 is fixed.
   - project: "issue/gitlab_templates-3421674"
     ref: "3421674-add-mariadb-simpletest-db"
     file: