Merge pull request #60998 from jpbetz/etcd-3.1.12

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Bump to etcd 3.1.12 to pick up critical fix

etcd [3.1.12](https://github.com/coreos/etcd/releases/tag/v3.1.12) (as well as 3.2.17 and 3.3.2) was released yesterday to fix a bug critical to kubernetes:

Fix [mvcc "unsynced" watcher restore operation](https://github.com/coreos/etcd/pull/9297).
- "unsynced" watcher is watcher that needs to be in sync with events that have happened.
- That is, "unsynced" watcher is the slow watcher that was requested on old revision.
- "unsynced" watcher restore operation was not correctly populating its underlying watcher group.
- Which possibly causes [missing events from "unsynced" watchers](https://github.com/coreos/etcd/issues/9086).

This will be backported to 1.9 as well.

Release note:
```release-note
Upgrade the default etcd server version to 3.1.12 to pick up critical etcd "mvcc "unsynced" watcher restore operation" fix.
```

cc @gyuho @wojtek-t @shyamjvs @timothysc @jdumars

test/e2e/framework/nodes_util.go

@@ -67,7 +67,7 @@ func etcdUpgradeGCE(target_storage, target_version string) error {
 		os.Environ(),
 		"TEST_ETCD_VERSION="+target_version,
 		"STORAGE_BACKEND="+target_storage,
-		"TEST_ETCD_IMAGE=3.1.11")
+		"TEST_ETCD_IMAGE=3.1.12")
 
 	_, _, err := RunCmdEnv(env, gceUpgradeScript(), "-l", "-M")
 	return err
@@ -107,7 +107,7 @@ func masterUpgradeGCE(rawV string, enableKubeProxyDaemonSet bool) error {
 		env = append(env,
 			"TEST_ETCD_VERSION="+TestContext.EtcdUpgradeVersion,
 			"STORAGE_BACKEND="+TestContext.EtcdUpgradeStorage,
-			"TEST_ETCD_IMAGE=3.1.11")
+			"TEST_ETCD_IMAGE=3.1.12")
 	} else {
 		// In e2e tests, we skip the confirmation prompt about
 		// implicit etcd upgrades to simulate the user entering "y".