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

Build failed. - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/43f9e09daaab44f98d83301868943f12 : SUCCESS in 3m 55s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/6185c6f097c84934b4f7a9bfd08b816c : FAILURE in 2m 55s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/edcf1e34e3af4986a334a0297511cf94 : SUCCESS in 4m 54s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/0dd3f74cbad9454ba86ab04a5060cc99 : SUCCESS in 5m 30s