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

Build failed. https://zuul.opendev.org/t/openstack/buildset/81c2e06c9b7a4e9ebd510cd551815c... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/46886b61062a46f88c11d0a6c9617603 : SUCCESS in 5m 29s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/6bc2fe2f272d4718a8b316434f9c744a : SUCCESS in 5m 10s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/e515273b28dd4581bb232e83d239f2ab : SUCCESS in 4m 17s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/fba09f2b29a746fba0862b2f96a9183b : FAILURE in 5m 12s