feat: add alertmanager to grafana datasources

cluster/components/observability/grafana/values.yaml

@@ -78,6 +78,16 @@ datasources:
         type: loki
         access: proxy
         url: http://loki-gateway:80
+      - name: Alertmanager
+        type: alertmanager
+        url: http://kube-prometheus-stack-alertmanager.monitoring:9093
+        editable: true
+        access: proxy
+        version: 2
+        jsonData:
+          implementation: prometheus
+          # Whether or not Grafana should send alert instances to this Alertmanager
+          handleGrafanaManagedAlerts: false
 dashboards:
   default:
     minio: