Merge pull request kubernetes-sigs#1431 from Penguin-zlh/doc/update-metrics-doc

doc: update Metrics doc

Author: k8s-ci-robot

site/content/en/docs/user/metrics-configuration.md

@@ -17,7 +17,7 @@ The [Metrics] is a [`kwok` Configuration][configuration] that allows users to de
 The YAML below shows all the fields of a Metrics resource:
 
 ``` yaml
-kind: Metrics
+kind: Metric
 apiVersion: kwok.x-k8s.io/v1alpha1
 metadata:
   name: <string>