See https://gitlab.com/gitlab-org/gitlab/-/issues/476575#note_2301971082 for more details - [x] Update `routes` to be `gitlab_main_cell`. - [x] Set `namespace_id` as the table's sharding key. Read [GitLab Cells Development Guidelines](https://docs.gitlab.com/ee/development/cells/#choose-either-the-gitlab_main_cell-or-gitlab_main_clusterwide-schema) for more details on how to work with sharding keys.