Monitoring: Fix resources dashboard

We lost the resources dashboard somehow. Get it back.

nixos/modules/monitoring/server/grafana-dashboards/resources-overview.json

@@ -22,6 +22,7 @@
   "editable": true,
   "fiscalYearStartMonth": 0,
   "graphTooltip": 1,
+  "id": 41,
   "links": [],
   "liveNow": false,
   "panels": [
@@ -294,6 +295,7 @@
         "noDataState": "no_data",
         "notifications": []
       },
+      "datasource": {},
       "description": "How much RAM is in use? Relative to available system memory.",
       "fieldConfig": {
         "defaults": {
@@ -852,6 +854,10 @@
         "noDataState": "no_data",
         "notifications": []
       },
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "description": "Network errors, drops etc. Should all be 0.",
       "fieldConfig": {
         "defaults": {
@@ -1162,6 +1168,10 @@
         "noDataState": "no_data",
         "notifications": []
       },
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "description": "How much user data do we store",
       "fieldConfig": {
         "defaults": {
@@ -1578,6 +1588,10 @@
       "type": "row"
     },
     {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "fieldConfig": {
         "defaults": {
           "color": {
@@ -1663,6 +1677,10 @@
       "type": "timeseries"
     },
     {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "fieldConfig": {
         "defaults": {
           "color": {
@@ -1748,6 +1766,10 @@
       "type": "timeseries"
     },
     {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "000000001"
+      },
       "fieldConfig": {
         "defaults": {
           "color": {