When a group in Foreman linked to two external user group is being synced, the sync is being case-sensitive and users where the case does not match get removed on the first sync and then added again on the next sync.

1. Should we prevent users from changing their username when they are linked to an LDAP auth source?
2. Should we make the group syncing case-insensitive?

Let's clarify with an example:

Username in Foreman: "admin-abc123", Username in AD: "Admin-Abc123" -> User gets removed.
This happens after the username was manually changed to lowercase.