chore: code cleanup with rector and php-cs-fixer

src/Controller/Api/NewsletterSubscriptionController.php

@@ -32,7 +32,7 @@ class NewsletterSubscriptionController extends AbstractController
     }
 
     #[Route('/newsletters', name: 'api_newsletters_all', methods: ['GET'])]
-    public function index():JsonResponse
+    public function index(): JsonResponse
     {
         return $this->json($this->newsletterManager->createListIdMapping(array_keys($this->mailjetLists)));
     }