AMBARI-8808. Resolve potential port conflicts with Hadoop daemons. alerts.json change. (swagle)

ambari-server/src/main/resources/common-services/AMS/0.1.0/alerts.json

@@ -35,7 +35,7 @@
         "enabled": true,
         "source": {
           "type": "PORT",
-          "uri": "8188",
+          "uri": "{{metric_collector_port}}",
           "default_port": 8188,
           "reporting": {
             "ok": {