Merge branch '4.4'

* 4.4:
  [ErrorRenderer] FlattenException cannot be final
  Fixing issue where worker-only middleware were run in all contexts
  [Messenger] Removing "sync" transport and replacing it with much nicer config trick
  Use port 465 for SES SMTP transport
  [DI] made the `%env(base64:...)%` processor able to decode base64url
  [VarDumper] improve displaying cut closures
  Set ReturnType of LockFactory to LockInterface
  [EventDispatcher] handle lazy-callable invokable

Author: nicolas-grekas

LockFactory.php

@@ -41,7 +41,7 @@ public function __construct(PersistingStoreInterface $store)
      * @param float|null $ttl         Maximum expected lock duration in seconds
      * @param bool       $autoRelease Whether to automatically release the lock or not when the lock instance is destroyed
      */
-    public function createLock(string $resource, ?float $ttl = 300.0, bool $autoRelease = true): Lock
+    public function createLock(string $resource, ?float $ttl = 300.0, bool $autoRelease = true): LockInterface
     {
         $lock = new Lock(new Key($resource), $this->store, $ttl, $autoRelease);
         $lock->setLogger($this->logger);