Add metrics service to kube-dns (#3852)

Metrics port is exposed through a service for CoreDNS but not for kube-dns.

roles/kubernetes-apps/ansible/templates/kubedns-svc.yml.j2

@@ -20,3 +20,6 @@ spec:
   - name: dns-tcp
     port: 53
     protocol: TCP
+  - name: metrics
+    port: 10055
+    protocol: TCP