Yorick Peterse authored
In a previous attempt (rolled back in gitlab-org/gitlab-ce!16021) we tried to migrate `issues.closed_at` from timestamp to timestamptz using a regular migration. This has a bad impact on GitLab.com and as such was rolled back. This commit re-implements the original migrations using generic background migrations, allowing us to still migrate the data in a single release but without a negative impact on availability. To ensure the database schema is up to date the background migrations are performed inline in development and test environments. We also make sure to not migrate that that doesn't need migrating in the first place or has already been migrated.