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

Build failed. https://zuul.opendev.org/t/openstack/buildset/ee9604f3266745a39267c50c153960... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/502f940fca2c4388aa42280079685272 : SUCCESS in 2m 52s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/c44ec9bbf1d841e9b2404014c84f5fdb : SUCCESS in 2m 28s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/48b7216c0c3f40c696c4c4d31a4ea593 : SUCCESS in 2m 47s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/cc58bb2036a546f99bc4f25ceb8ad65e : RETRY_LIMIT in 2s