cert-manager: 1.20.3 -> 1.21.0

Change-Id: I50161b8cfd621c1b07de87358fe8c14d1b14f711
diff --git a/charts/cert-manager/templates/service.yaml b/charts/cert-manager/templates/service.yaml
index 360ec64..3dedc68 100644
--- a/charts/cert-manager/templates/service.yaml
+++ b/charts/cert-manager/templates/service.yaml
@@ -28,8 +28,7 @@
   ports:
   - protocol: TCP
     port: 9402
-    name: tcp-prometheus-servicemonitor
-    targetPort: {{ .Values.prometheus.servicemonitor.targetPort }}
+    name: http-metrics
   selector:
     app.kubernetes.io/name: {{ include "cert-manager.name" . }}
     app.kubernetes.io/instance: {{ .Release.Name }}