[Openstack-stable-maint] Stable check of openstack/tooz for ref refs/heads/stable/train failed

Build failed. https://zuul.opendev.org/t/openstack/buildset/3e1217e63e7f4ca48aaca5dc472a0d... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/e5c94cdbcab844b59437e13867ead7c8 : SUCCESS in 5m 11s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/1223864d9a06437e8e2b9a555ab6be6a : SUCCESS in 5m 20s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/15c22516295f4f5b977c66332c978409 : SUCCESS in 5m 02s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/5c8047b5c9a3492fadbbf5d019523861 : FAILURE in 4m 20s