[cern] k8s_fedora: Explicitly set etcd authentication
Cherry-pick: https://review.openstack.org/#/c/557679/
Set client and peer auth to true and add trusted_ca configuration to enable authentication via certs for both clients and other etcd members.
Change-Id: I1d0fbd6f89dc2e95e016299c5ce0c68eb4fe8e1a Closes-Bug: #1759813