[cern] Clean-up CA certs for etcd and front-proxy
upstream: https://review.opendev.org/c/openstack/magnum/+/915775
When the cluster is deleted, these certificates should be removed as well.
Closes-Bug: #2061314 Change-Id: I5ea2e58abd4632fe3a290765cadbbaf72fce9010
closes: #52
Edited by Spyridon Trigazis