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

Build failed. https://zuul.opendev.org/t/openstack/buildset/cd0fb2313dce43e7ae2820fa279831... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/fc47412df4ae44909d72dbf344b36a2f : POST_FAILURE in 15m 25s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/b9721d30693f44d286194c7262e3f69e : SUCCESS in 12m 57s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/ed0c1a5f803b4cf19cea489e1b7ed704 : POST_FAILURE in 31m 32s