[DPE-3383] Fix dashboard 6/edge (#343)

## Issue
Dashboard wasn't showing metrics

## Solution
Update dashboard to show metrics
![Screenshot 2024-01-29 at 18 03
44](https://github.com/canonical/mongodb-operator/assets/32723809/443d753e-c54c-4ea1-a3fb-59e4e6cc84bf)

src/grafana_dashboards/MongoDB_ReplSet_Summary.json

@@ -122,7 +122,7 @@
                         "type": "datasource",
                         "uid": "${prometheusds}"
                     },
-                    "expr": "count by(set) (group by(service_name, set) (mongodb_mongod_replset_number_of_members{cluster=~\"$cluster\",juju_application=\"$juju_application\",juju_model=\"$juju_model\",juju_model_uuid=\"$juju_model_uuid\",juju_unit=\"$juju_unit\",set=~\"$replset\"} or mongodb_mongod_replset_my_state{cluster=~\"$cluster\",juju_application=\"$juju_application\",juju_model=\"$juju_model\",juju_model_uuid=\"$juju_model_uuid\",juju_unit=\"$juju_unit\",set=~\"$replset\"}))",
+                    "expr": "mongodb_mongod_replset_number_of_members{juju_application=~\"$juju_application\",juju_model=~\"$juju_model\",juju_model_uuid=~\"$juju_model_uuid\",juju_unit=~\"$juju_unit\"} ",
                     "interval": "5m",
                     "intervalFactor": 1,
                     "legendFormat": "",
@@ -3130,22 +3130,19 @@
         ]
     },
     "time": {
-        "from": "2023-03-27T08:51:52.293Z",
-        "to": "2023-04-12T08:51:52.293Z"
+        "from": "now-12h",
+        "to": "now"
     },
     "timepicker": {
         "hidden": false,
         "now": true,
         "refresh_intervals": [
+            "1s",
             "5s",
-            "10s",
-            "30s",
             "1m",
             "5m",
-            "15m",
-            "30m",
             "1h",
-            "2h",
+            "6h",
             "1d"
         ],
         "time_options": [