TT#122050 Fix main link on ngcp-panel Dashboard->"View Statistics"

After the recent migration to new Grafana the old link produces: 'Dashboard not found'.

It is a fixup for the commit e4cfc9842a
> TT#51065 Update grafana dashboard URLs for grafana 5.x

Let's also sync param 'ngcp_grafana_admin=no' for all links.

Change-Id: I7be1a021cff154093ee41bc57bbbb7482eda9954

share/templates/widgets/admin_system_overview.tt

@@ -55,7 +55,7 @@ enqueLists.push([{
             </ul>
         </div>
         <div class="plan-actions">
-            <a href="/grafana/dashboard/file/system-statistics" class="btn">[% c.loc('View Statistics') %]</a>
+            <a href="/grafana/d/system-statistics?ngcp_grafana_admin=no" class="btn">[% c.loc('View Statistics') %]</a>
         </div>
     </div>
 </div>