Merge pull request #43569 from alejandroEsc/ae/localup/etcd3

Automatic merge from submit-queue (batch tested with PRs 43149, 41399, 43154, 43569, 42507)

allow etcd2/3 choice when bringing up a local cluster, default to etcd3

**What this PR does / why we need it**: local-up-cluster currently doesn't allow you to select which etcd version to use, here we allow you to select one, since k8s is moving towards etcd3 we suggest it to be the default.

**Special notes for your reviewer**: Note, i didnt realize this until i had used https://github.com/kubernetes/kubernetes/pull/42656 which made it immediately clear.

**Release note**:
```
NONE
```

hack/local-up-cluster.sh

@@ -62,7 +62,7 @@ HOSTNAME_OVERRIDE=${HOSTNAME_OVERRIDE:-"127.0.0.1"}
 CLOUD_PROVIDER=${CLOUD_PROVIDER:-""}
 CLOUD_CONFIG=${CLOUD_CONFIG:-""}
 FEATURE_GATES=${FEATURE_GATES:-"AllAlpha=true"}
-
+STORAGE_BACKEND=${STORAGE_BACKEND:-"etcd3"}
 # enable swagger ui
 ENABLE_SWAGGER_UI=${ENABLE_SWAGGER_UI:-false}
 
@@ -449,6 +449,7 @@ function start_apiserver {
       --tls-ca-file="${CERT_DIR}/server-ca.crt" \
       --insecure-bind-address="${API_HOST_IP}" \
       --insecure-port="${API_PORT}" \
+      --storage-backend=${STORAGE_BACKEND} \
       --etcd-servers="http://${ETCD_HOST}:${ETCD_PORT}" \
       --service-cluster-ip-range="${SERVICE_CLUSTER_IP_RANGE}" \
       --feature-gates="${FEATURE_GATES}" \