Automatic merge from submit-queue

Delete duplicated code

The code block below is called twice sequentially in func `doTestPlugin`.
.
```go
 	if _, err := os.Stat(path); err != nil {
 		if os.IsNotExist(err) {
 			t.Errorf("SetUp() failed, volume path not created: %s", path)
 		} else {
 			t.Errorf("SetUp() failed: %v", err)
 		}
 	}
```