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

Build failed. https://zuul.opendev.org/t/openstack/buildset/3760b924852f4f68930684cfbc60ff... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/aae4bdf2568a42f4837d7b527580fa1d : SUCCESS in 5m 16s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/2340750f9349403ab4f0f02676a168e2 : SUCCESS in 5m 20s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/9541774ee4514b98ae8e29411723e2cf : FAILURE in 4m 54s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/0bc00fa0078146799a776d1fbfbf7747 : SUCCESS in 5m 28s