Fix OAuth, LDAP and SAML SSO when regular sign-ups are disabled
What does this MR do?
Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/31294 for the 9-1-stable
branch.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/31294 for the 9-1-stable
branch.