Do not try to show the database dashboard, when clicked on one of the

children node. This implementation will allow to add new nodes at server
level without modifying the dashboard code. I found the issue during the
pgAgent Jobs node implementation.

web/pgadmin/dashboard/templates/dashboard/js/dashboard.js

@@ -76,7 +76,9 @@ function(r, $, pgAdmin, _, Backbone) {
                     default:
                         url = '{{ url_for('dashboard.index') }}'
                                 + treeHierarchy.server._id
-                                + '/' + treeHierarchy.database._id;
+                        if ('database' in treeHierarchy) {
+                          url += '/' + treeHierarchy.database._id;
+                        }
                         break;
                 }
             }