Comment 4 for bug 1746016

I haven't seen this happen in a while, and at the moment I suspect it was related to infrastructure problems discussed here: http://eavesdrop.openstack.org/irclogs/%23openstack-infra/%23openstack-infra.2018-01-31.log.html#t2018-01-31T16:43:42

Marking this invalid for now, we can reopen if necessary.