Wait longer before exiting _podman_client
    
    At the end of _podman_client we create a mutex that we want the
    server to pick up. If we exit too soon, the mutex goes away and
    the server test fails. 5 seconds turns out to be not enough of a
    wait because, although the server retries the lock call every
    5 seconds, it can hit `api_call_2 failed` and wait 10 seconds
    before retrying. Let's wait 30 seconds just to be safe.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>