Merge pull request #38917 from foxyriver/if-statement-must-be-true

Automatic merge from submit-queue (batch tested with PRs 38426, 38917, 38891, 38935)

if statement must be true

**What this PR does / why we need it**:

if len(metrics.Items)==0, the function would been returned. so the statement if len(metrics.Items) > 0 is redudant, it must be true.

**Special notes for your reviewer**:

**Release note**:

```release-note
```

pkg/controller/podautoscaler/metrics/metrics_client.go

@@ -122,10 +122,7 @@ func (h *HeapsterMetricsClient) GetResourceMetric(resource v1.ResourceName, name
 		}
 	}
 
-	timestamp := time.Time{}
-	if len(metrics.Items) > 0 {
-		timestamp = metrics.Items[0].Timestamp.Time
-	}
+	timestamp := metrics.Items[0].Timestamp.Time
 
 	return res, timestamp, nil
 }