[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/fe30a1b29ee0407fbc680b70b8bcee53 : SUCCESS in 4m 17s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/cf3f98141e1e437f9e1ed4bd8a1d355f : FAILURE in 4m 25s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/f4ecbc88bbc44460b151fec4162d47dc : FAILURE in 4m 54s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/0c88b81e44a64545af16a3a1df53a069 : FAILURE in 5m 03s