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

Build failed. https://zuul.opendev.org/t/openstack/buildset/dbabc098b6b14a93bac132806a6a72... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/377693d9715346c99a819fccecf45847 : SUCCESS in 5m 22s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/776161ac845247bfb6e61246998e3dfe : SUCCESS in 7m 32s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/5aba5b4cd8b749b89dfda859344679ed : SUCCESS in 7m 39s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/46135a79a7c746f8a077d1f4b8fc2e68 : FAILURE in 4m 53s