[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/a3d7d97a1ed540a6a70a3bb196b349... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/f2464b424a054f84a930ea9ea8af0928 : SUCCESS in 4m 40s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/b18657678a2d4d07bea5396cb298b5e3 : SUCCESS in 4m 31s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/8e0d64a2669c46579a4181445ac346ee : SUCCESS in 4m 10s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/0edaccb9a0a64ada97dd8914dfe9dc0f : FAILURE in 3m 51s