[cern] Ensure kube-apiserver TLS connection to etcd server

CherryPick: https://review.opendev.org/c/openstack/magnum/+/854394

Improve kube-bench remediations 1.2.26 and 1.2.29

Story: 2010248
Task: 46091

Change-Id: I8349265d0fc23513a96328669debe5b554db4df6

magnum/drivers/common/templates/kubernetes/fragments/configure-kubernetes-master.sh

@@ -346,6 +346,7 @@ KUBE_API_ADDRESS="--bind-address=0.0.0.0 --secure-port=$KUBE_API_PORT"
 KUBE_API_ARGS="$KUBE_API_ARGS --authorization-mode=Node,RBAC --tls-cert-file=$CERT_DIR/server.crt"
 KUBE_API_ARGS="$KUBE_API_ARGS --tls-private-key-file=$CERT_DIR/server.key"
 KUBE_API_ARGS="$KUBE_API_ARGS --client-ca-file=$CERT_DIR/ca.crt"
+KUBE_API_ARGS="$KUBE_API_ARGS --etcd-cafile=$CERT_DIR/ca.crt --etcd-certfile=$CERT_DIR/server.crt --etcd-keyfile=$CERT_DIR/server.key"
 KUBE_API_ARGS="$KUBE_API_ARGS --service-account-key-file=${CERT_DIR}/service_account.key"
 KUBE_API_ARGS="$KUBE_API_ARGS --service-account-signing-key-file=${CERT_DIR}/service_account_private.key"
 KUBE_API_ARGS="$KUBE_API_ARGS --service-account-issuer=https://kubernetes.default.svc.cluster.local"