Use kokkuri v1.6.0 image
That image supports Dockerfiles.
Bug: T326569
How to register an account on GitLab. To prevent spam, new accounts are locked until approved by an admin or the approver bot. You can also file an unlock request to expedite access.
Support: mw:GitLab, how to host a project on GitLab, #wikimedia-gitlab on libera.chat, #GitLab on Phabricator.
That image supports Dockerfiles.
Bug: T326569