--skip-migration-test option on 12 release

I would like to know if there is still a way to skip the migration test on nextcloud 12 release.

I’ve seen that “–skip-migration-test” is not available since 10 release. This functionnality really disapeared?

Yes. → https://github.com/nextcloud/server/issues/3616

So, why have I still a message like this while I’m upgrading my nexctloud instance? Upgrade: Insufficent privilege for pg_namespace relation

Why Nextcloud need to access to pg_namespace postgresql table just for upgrading?