Add database config sanity check to `gitlab-rake gitlab:check`
We recently dealt with an issue where a user's external Postgres database configuration causing the same pipelines to be triggered multiple times. In this particular case, they have
default_transaction_isolation configured as
repeatable read instead of
read committed (internal only ZD ref: https://gitlab.zendesk.com/agent/tickets/119156)
I've documented the troubleshooting error in our documentation here: omnibus-gitlab!3359 (diffs)
It would be great if our
gitlab:check can catch these kinds of potential database configuration issues.