Don't try mirroring if we failed generating private key
    
    If we failed generating the private key there is no point in trying
    to push anything with it.
    I believe this also fixes the issue we've seen with the mirroring
    service as the mirroring task was failing this was impacting other
    tasks while at it.
    
    Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>