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

Build failed. https://zuul.opendev.org/t/openstack/buildset/8df8270b98dd445a9251298747eb10... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/e71a27490b4c4e9d886f1401ebe7d892 : TIMED_OUT in 30m 50s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/73161d58f91b44289ff89f9740d582b2 : SUCCESS in 3m 03s - openstack-tox-py38 https://zuul.opendev.org/t/openstack/build/1ff297a527e84f7e803323a4607d2522 : TIMED_OUT in 40m 44s