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

Build failed. https://zuul.opendev.org/t/openstack/buildset/e53a5f1f0d674f539449061925aaf0... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/e91c4c7201284be28ae6b0a3e2b5ac62 : SUCCESS in 5m 14s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/af5a672670bb4508a45446c5a5f429c6 : SUCCESS in 5m 14s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/56309643c7c44d6b80bc0e901055a768 : SUCCESS in 4m 08s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/635a43e643c34651aa2e5ed90cd07e5b : FAILURE in 4m 04s