Fix 'Kirby\Panel\Panel::area(): Argument Daandelange#2 ($area) must b…

…e of type array|string, null given'

Fixes Daandelange#37

index.php

@@ -21,7 +21,7 @@
     'areas' => [
         'simplestats' => function ($kirby) {
 
-            if(!$kirby->user() || !$kirby->user()->hasSimpleStatsPanelAccess()) return null;
+            if(!$kirby->user() || !$kirby->user()->hasSimpleStatsPanelAccess()) return [];
 
             return [
                 // label for the menu and the breadcrumb