fluentd add port promtheus and health check

fluentd readiness and liveness health check can use fluent-plugin-prometheus port

cluster/addons/fluentd-elasticsearch/fluentd-es-ds.yaml

@@ -89,6 +89,20 @@ spec:
           readOnly: true
         - name: config-volume
           mountPath: /etc/fluent/config.d
+        ports:
+        - containerPort: 24231
+          name: prometheus
+          protocol: TCP
+        livenessProbe:
+          tcpSocket:
+            port: prometheus
+          initialDelaySeconds: 5
+          timeoutSeconds: 10
+        readinessProbe:
+          tcpSocket:
+            port: prometheus
+          initialDelaySeconds: 5
+          timeoutSeconds: 10
       terminationGracePeriodSeconds: 30
       volumes:
       - name: varlog