[TASK] Ensure parentTable key is set before comparison

Check for the existence of the 'parentTable' key
in the configuration array before comparing it.
This prevents potential undefined index errors.

Classes/Service/AdditionalContentService.php

@@ -258,7 +258,7 @@ protected function getConfigs(string $cType, string $parentTable = ''): array
     {
         $configs = $this->processedAdditionalTableConfig[$cType] ?? $this->processedAdditionalTableConfig[$cType] ?? [];
         foreach ($configs as $key => $config) {
-            if ($parentTable != '' && $config['parentTable'] !== $parentTable) {
+            if ($parentTable != '' && isset($config['parentTable']) && $config['parentTable'] !== $parentTable) {
                 unset($configs[$key]);
             }
         }