[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/af822e46cb6b43cdb483c647265b3f9b : SUCCESS in 7m 34s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/c3d6f006e7eb4bbdb217e98bac20d767 : FAILURE in 8m 19s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/ef5471910dae48faade7091c7c6ded75 : FAILURE in 8m 43s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/e35ebe206ef0429b9fa38569339bcc3a : FAILURE in 6m 57s