Merge pull request kubernetes#91925 from wenjiaswe/etcdHostName

ETCD_NAME in migrate-if-needed.sh should be the same as etcd.manifest

Author: k8s-ci-robot

cluster/images/etcd/migrate-if-needed.sh

@@ -46,7 +46,7 @@ set -o nounset
 BUNDLED_VERSIONS="3.0.17, 3.1.12, 3.2.24, 3.3.17, 3.4.7"
 
 # shellcheck disable=SC2039
-ETCD_NAME="${ETCD_NAME:-etcd-$HOSTNAME}"
+ETCD_NAME="${ETCD_NAME:-etcd-${ETCD_HOSTNAME:-$(hostname -s)}}"
 if [ -z "${DATA_DIRECTORY:-}" ]; then
   echo "DATA_DIRECTORY variable unset - unexpected failure"
   exit 1