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

Build failed. https://zuul.opendev.org/t/openstack/buildset/74db2e8dbeec4a348fe4dee543666b... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/e4031efcf8d9470db43c1d196a8ef5c9 : SUCCESS in 4m 58s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/567172b872aa4769910207cb0ef281a8 : SUCCESS in 4m 51s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/a8526ba80d9d49ddb9beaacfb1af11df : SUCCESS in 3m 03s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/ae5fe408290b46c29971a22f74087e38 : FAILURE in 3m 00s