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

Build failed. https://zuul.opendev.org/t/openstack/buildset/89cf3e878bff4812884ff53da8a036... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/3e42bd1d282c4aa9b15323e0f9e91b77 : FAILURE in 4m 48s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/3c128d31d8f94f96868f53232bc5aa5f : FAILURE in 3m 26s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/4773b631760a4fdb9b04558ef22eb16f : FAILURE in 2m 26s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/25117e92ec9443bc877ef0bd929c83bf : FAILURE in 3m 18s