Fix post push message when using Kerberos

What does this MR do?

Takes Kerberos into account when printing the post push message after moving a project to another namespace.

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/11608

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content