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

Build failed. https://zuul.opendev.org/t/openstack/buildset/5a66da8dd62c49edb8704e016736e0... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/6d6132d1dda2407e9a8c95fb7cd744ab : SUCCESS in 4m 35s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/114c10127c124f0fa02f5d43aaea6b5c : SUCCESS in 4m 40s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/0c046754ff7c44b89c3ff26653aa008e : SUCCESS in 4m 29s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/efb17860b05245759fe94da34b840bc2 : FAILURE in 4m 02s