Merge pull request #59728 from wgliang/master.append

Automatic merge from submit-queue (batch tested with PRs 59740, 59728, 60080, 60086, 58714). 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>.

more concise to merge the slice

**What this PR does / why we need it**:
more concise to merge the slice

**Special notes for your reviewer**:

pkg/volume/rbd/rbd.go

@@ -590,9 +590,7 @@ func (r *rbdVolumeProvisioner) Provision() (*v1.PersistentVolume, error) {
 		switch dstrings.ToLower(k) {
 		case "monitors":
 			arr := dstrings.Split(v, ",")
-			for _, m := range arr {
-				r.Mon = append(r.Mon, m)
-			}
+			r.Mon = append(r.Mon, arr...)
 		case "adminid":
 			r.adminId = v
 		case "adminsecretname":