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

Build failed. - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/cb2aa3db4618458cac94312af7c66b3d : SUCCESS in 5m 57s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/425f34adb41d484e85d8200179eb226e : FAILURE in 5m 25s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/4817a68fd3874e9e8fd4f9c72c78ee35 : FAILURE in 4m 27s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/723418c522564774bf6182d49fc93d6a : FAILURE in 5m 02s