Fix bug in using CSRF when deleting an account.

module/VuFind/src/VuFind/Controller/MyResearchController.php

@@ -1743,7 +1743,7 @@ class MyResearchController extends AbstractBase
                 );
             } else {
                 // After successful token verification, clear list to shrink session:
-                $this->csrf->trimTokenList(0);
+                $csrf->trimTokenList(0);
             }
             $user->delete(
                 $config->Authentication->delete_comments_with_user ?? true