fix: Add metric port to pods and service (#1199)

This allows the usage of Prometheus PodMonitors and/or ServiceMonitors
to configure scraping of metrics.  This is often preferred over the
annotations on the pods.  This is also more inline with the rest of
Knative.

- Add metric port definition to both gateway pods and controller pods.
- Add metric port to controller service

NOTE: Did not add metric port to gateway services as those often are
exposed and exposing the metrics via those services is probably not
desired in most cases.

config/300-controller.yaml

@@ -70,6 +70,9 @@ spec:
           - name: http2-xds
             containerPort: 18000
             protocol: TCP
+          - name: metrics
+            containerPort: 9090
+            protocol: TCP
           readinessProbe:
             grpc:
               port: 18000
@@ -115,6 +118,10 @@ spec:
       port: 18000
       protocol: TCP
       targetPort: 18000
+    - name: http-metrics
+      port: 9090
+      protocol: TCP
+      targetPort: 9090
   selector:
     app: net-kourier-controller
   type: ClusterIP

config/300-gateway.yaml

@@ -73,6 +73,9 @@ spec:
             - name: https-probe
               containerPort: 9443
               protocol: TCP
+            - name: metrics
+              containerPort: 9000
+              protocol: TCP
           securityContext:
             allowPrivilegeEscalation: false
             readOnlyRootFilesystem: false