return an error for missing metric templates and count that towards the failure threshold

Signed-off-by: LiZhenCheng9527 <lizhencheng6@huawei.com>

pkg/controller/scheduler_metrics.go

@@ -306,6 +306,9 @@ func (c *Controller) runMetricChecks(canary *flaggerv1.Canary) bool {
 					canary.Name, canary.Namespace, metric.Name, val, metric.Threshold)
 				return false
 			}
+		} else if metric.Name != "request-success-rate" && metric.Name != "request-duration" {
+			c.recordEventErrorf(canary, "Metric query failed for no usable metrics template were configured")
+			return false
 		}
 	}