This distro release reached its EOL December 31, 2021. We are removing
it from our CI system as people should really stop testing on it. They
can use CentOS 8 Stream or other alternatives instead.
Depends-On: https://review.opendev.org/c/opendev/base-jobs/+/827181
Change-Id: I13e8185b7839371a9f9043b715dc39c6baf907d5
dce378a6b4