e.g. https://integration.wikimedia.org/ci/job/mwext-php70-phan-docker/23013/console, https://integration.wikimedia.org/ci/job/mwext-php70-phan-docker/23011/console
20:16:10 docker: failed to register layer: error creating overlay mount to /var/lib/docker/overlay2/75f01b933a0e237ff39ceb13a6cc1de30284f4f0d8741a1a22cdf0842a90ff3b/merged: no such file or directory.