Dashboard rationalization

Change-Id: Ibc51a3c0839968678e930fbc7b88218988fc0dc2
Closes-bug: PROD-20091
diff --git a/grafana/files/grafana_dashboards/grafana_prometheus.json b/grafana/files/grafana_dashboards/grafana_prometheus.json
index a21187c..68a2bf7 100644
--- a/grafana/files/grafana_dashboards/grafana_prometheus.json
+++ b/grafana/files/grafana_dashboards/grafana_prometheus.json
@@ -5,7 +5,7 @@
       {
         "$$hashKey": "object:143",
         "builtIn": 1,
-        "datasource": "-- Grafana --",
+        "datasource": "prometheus",
         "enable": true,
         "hide": true,
         "iconColor": "rgba(0, 211, 255, 1)",
@@ -17,7 +17,7 @@
   "editable": true,
   "gnetId": null,
   "graphTooltip": 0,
-  "id": 134,
+  "id": null,
   "iteration": 1529426501345,
   "links": [],
   "panels": [
@@ -44,7 +44,7 @@
         "rgba(237, 129, 40, 0.89)",
         "rgba(50, 172, 45, 0.97)"
       ],
-      "datasource": "prometheus",
+      "datasource": null,
       "format": "none",
       "gauge": {
         "maxValue": 100,
@@ -125,7 +125,7 @@
         "rgba(237, 129, 40, 0.89)",
         "rgba(50, 172, 45, 0.97)"
       ],
-      "datasource": "prometheus",
+      "datasource": null,
       "format": "none",
       "gauge": {
         "maxValue": 100,
@@ -206,7 +206,7 @@
         "rgba(237, 129, 40, 0.89)",
         "rgba(50, 172, 45, 0.97)"
       ],
-      "datasource": "prometheus",
+      "datasource": null,
       "format": "none",
       "gauge": {
         "maxValue": 100,
@@ -287,7 +287,7 @@
         "rgba(237, 129, 40, 0.89)",
         "rgba(50, 172, 45, 0.97)"
       ],
-      "datasource": "prometheus",
+      "datasource": null,
       "format": "none",
       "gauge": {
         "maxValue": 100,
@@ -379,7 +379,7 @@
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "prometheus",
+      "datasource": null,
       "fill": 1,
       "gridPos": {
         "h": 7,
@@ -464,7 +464,7 @@
       "bars": false,
       "dashLength": 10,
       "dashes": false,
-      "datasource": "prometheus",
+      "datasource": null,
       "fill": 1,
       "gridPos": {
         "h": 7,