Document mailhog instance
Once https://gitlab.developers.cam.ac.uk/uis/devops/admin/issues/88 is closed, we should document the service in the guidebook.
GitLab will be updated on 12-Feb-2026 between 12:00 and 14:00. There may be small periods of service instability.
Once https://gitlab.developers.cam.ac.uk/uis/devops/admin/issues/88 is closed, we should document the service in the guidebook.