Improve tests with cluster health and status

[bissquit]

Is your feature request related to a problem? Please describe.
We need more control over multi node etcd installation

Describe the solution you'd like
The following commands give us more information about cluster health:

# https://etcd.io/docs/v3.5/tutorials/how-to-check-cluster-status/
# https://platform9.com/kb/kubernetes/how-to-find-etcd-leader-and-check-etcd-health
cd /etc/ssl/private
etcdctl --endpoints=172.28.0.4:2379,172.28.0.2:2379,172.28.0.3:2379 --cacert=ca.pem --cert=client.pem --key=client-key.pem  --write-out=table endpoint status
etcdctl --endpoints=172.28.0.4:2379,172.28.0.2:2379,172.28.0.3:2379 --cacert=ca.pem --cert=client.pem --key=client-key.pem  --write-out=table endpoint health
etcdctl --endpoints=172.28.0.4:2379,172.28.0.2:2379,172.28.0.3:2379 --cacert=ca.pem --cert=client.pem --key=client-key.pem  --write-out=table member list

Also it could be useful to check cluster working by moving leader to another node and checking how cluster operates:

etcdctl move-leader --help

Describe alternatives you've considered
Not applicable

Additional context
Not applicable