FreeIPA: handle unexpected auto-login to webUI
    
    There are cases where we get logged back into the FreeIPA web UI
    automatically by a stale kerberos ticket or something. If we're
    logged in as the *right* user, let's just treat this as a soft
    failure and continue with the test.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>