add service monitor to grafana

manifests/grafana-service.yaml

@@ -1,5 +1,7 @@
 apiVersion: v1
 kind: Service
+labels:
+  app: grafana
 metadata:
   name: grafana
   namespace: monitoring

manifests/grafana-serviceMonitor.yaml

@@ -0,0 +1,12 @@
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: grafana
+  namespace: monitoring
+spec:
+  endpoints:
+  - interval: 15s
+    port: http
+  selector:
+    matchLabels:
+      app: grafana