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

Build failed. https://zuul.opendev.org/t/openstack/buildset/1f463bdb3893435ebea5e6bfc3a60d... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/eff6cdc9e71f4fab94c967cd8235aa5e : SUCCESS in 6m 00s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/ebc9fa5fd616409397b478253816fb24 : SUCCESS in 5m 16s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/63737d5f59d347e2aea693ed1272172d : SUCCESS in 6m 59s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/1e207cd9340d4196a15ac541ab305d35 : FAILURE in 4m 08s