Provide scale-set listener metrics (#2559)

Co-authored-by: Tingluo Huang <tingluohuang@github.com>
Co-authored-by: Bassem Dghaidi <568794+Link-@users.noreply.github.com>

charts/gha-runner-scale-set-controller/templates/deployment.yaml

@@ -65,8 +65,25 @@ spec:
         {{- with .Values.flags.updateStrategy }}
         - "--update-strategy={{ . }}"
         {{- end }}
+        {{- if .Values.metrics }}
+        {{- with .Values.metrics }}
+        - "--listener-metrics-addr={{ .listenerAddr }}"
+        - "--listener-metrics-endpoint={{ .listenerEndpoint }}"
+        - "--metrics-addr={{ .controllerManagerAddr }}"
+        {{- end }}
+        {{- else }}
+        - "--listener-metrics-addr=0"
+        - "--listener-metrics-endpoint="
+        - "--metrics-addr=0"
+        {{- end }}
         command:
         - "/manager"
+        {{- with .Values.metrics }}
+        ports:
+        - containerPort: {{regexReplaceAll ":([0-9]+)" .controllerManagerAddr "${1}"}}
+          protocol: TCP
+          name: metrics
+        {{- end }}
         env:
         - name: CONTROLLER_MANAGER_CONTAINER_IMAGE
           value: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"