Change metric to retrieve hostname

Author: technowhizz

etc/kayobe/kolla/config/grafana/dashboards/openstack/openstack.json

@@ -3076,15 +3076,15 @@
           "type": "prometheus",
           "uid": "${datasource}"
         },
-        "definition": "label_values(node_cpu_seconds_total,instance)",
+        "definition": "label_values(node_uname_info,nodename)",
         "hide": 0,
         "includeAll": true,
         "label": "Host",
         "multi": true,
         "name": "host",
         "options": [],
         "query": {
-          "query": "label_values(node_cpu_seconds_total,instance)",
+          "query": "label_values(node_uname_info,nodename)",
           "refId": "PrometheusVariableQueryEditor-VariableQuery"
         },
         "refresh": 2,