Merge branch '6.3' into 6.4

* 6.3:
  [Form] Fix merging params & files when "multiple" is enabled
  [HttpFoundation] Do not swallow trailing `=` in cookie value
  Handle Sendinblue error responses without a message key
  [Serializer] Fix collecting only first missing constructor argument
  [Messenger] Simplify code
  [Messenger] Fix graceful exit
  [Messenger] Fix DoctrineOpenTransactionLoggerMiddleware
  [Translation] Add missing return type
  [Validator] add missing catalan translations

Author: nicolas-grekas

Messenger/DoctrineOpenTransactionLoggerMiddleware.php

@@ -24,6 +24,8 @@
  */
 class DoctrineOpenTransactionLoggerMiddleware extends AbstractDoctrineMiddleware
 {
+    private bool $isHandling = false;
+
     public function __construct(
         ManagerRegistry $managerRegistry,
         string $entityManagerName = null,
@@ -34,6 +36,12 @@ public function __construct(
 
     protected function handleForManager(EntityManagerInterface $entityManager, Envelope $envelope, StackInterface $stack): Envelope
     {
+        if ($this->isHandling) {
+            return $stack->next()->handle($envelope, $stack);
+        }
+
+        $this->isHandling = true;
+
         try {
             return $stack->next()->handle($envelope, $stack);
         } finally {
@@ -42,6 +50,7 @@ protected function handleForManager(EntityManagerInterface $entityManager, Envel
                     'message' => $envelope->getMessage(),
                 ]);
             }
+            $this->isHandling = false;
         }
     }
 }