Catch EmptyResult exception in update_idranges
    
    If no results are returned then find_entries will raise
    EmptyResult and not NotFound. NotFound is returned if
    the search base doesn't exist.
    
    The test for not entries can be removed as well since this
    is the EmptyResult case. In case of a NotFound this will
    be handled by the ExecutionError clause.
    
    Found with https://pagure.io/freeipa/issue/8555
    
    Signed-off-by: Rob Crittenden <rcritten@redhat.com>
    Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>