Revert "Remove duplicated code as it is already part of utils.stateLoadCallback"

This reverts commit 395b1b6c1f.

Signed-off-by: Christian König <ckoenig@posteo.de>

scripts/pi-hole/js/groups.js

@@ -99,6 +99,11 @@ $(function () {
     stateLoadCallback: function () {
       var data = utils.stateLoadCallback("groups-table");
 
+      // Return if not available
+      if (data === null) {
+        return null;
+      }
+
       // Reset visibility of ID column
       data.columns[0].visible = false;
       // Apply loaded state to table