Make wait_for_entry raise exceptions
    
    Instead of only logging errors when timeout is reached or query for the
    entry fails for other reasons, `wait_for_entry` should raise exceptions
    so that we can handle them in caller or let them propagate and fail
    early.
    
    https://pagure.io/freeipa/issue/6739
    
    Reviewed-By: Martin Basti <mbasti@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>