Add networkPolicies for alertmanager, grafana, prometheus-operator and prometheus

Signed-off-by: GitHub <noreply@github.com>
(cherry picked from commit 86e16b539cc57710b50f4692848cab5645e3d2bc)

jsonnet/kube-prometheus/components/prometheus-operator.libsonnet

@@ -72,6 +72,32 @@ function(params)
       },
     },
 
+    networkPolicy: {
+      apiVersion: 'networking.k8s.io/v1',
+      kind: 'NetworkPolicy',
+      metadata: po.service.metadata,
+      spec: {
+        podSelector: {
+          matchLabels: po._config.selectorLabels,
+        },
+        policyTypes: ['Egress', 'Ingress'],
+        egress: [{}],
+        ingress: [{
+          from: [{
+            podSelector: {
+              matchLabels: {
+                'app.kubernetes.io/name': 'prometheus',
+              },
+            },
+          }],
+          ports: std.map(function(o) {
+            port: o.port,
+            protocol: 'TCP',
+          }, po.service.spec.ports),
+        }],
+      },
+    },
+
     service+: {
       spec+: {
         ports: [