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

Build failed. https://zuul.opendev.org/t/openstack/buildset/c22b52d5fa57472185023de3da5d98... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/1c8bd56b1a4c403f9c705eb8c65aa158 : SUCCESS in 5m 52s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/616a9e9a9e9b4678a6c612d085db6bd0 : SUCCESS in 5m 12s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/be4d9daab3bf405fa33948b1e14a6c08 : SUCCESS in 5m 15s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/3fb954f4079a4ec180acdbcec07b8f29 : FAILURE in 4m 22s