Merge branch '6.4' into 7.0

* 6.4:
  fix tests
  fix merge
  fix typo
  Change ProxyCacheWarmer::warmUp signature
  CS fix
  [Serializer] Keep stack trace for enum value denormalizer error
  add the MailPace transport to the UnsupportedSchemeException
  add the Phrase translation provider to the UnsupportedSchemeException
  [Serializer] Fix partial denormalization with missing constructor arguments
  [Serializer] Moves dummy to fixtures folder
  [HttpKernel] Don't validate partially denormalized object
  fix(mailjet-smtp): disable tls for mailjet as it should use starttls instead

Author: xabbuh

Tests/DeprecationErrorHandler/DeprecationTest.php

@@ -265,7 +265,7 @@ private static function removeDir($dir)
         rmdir($dir);
     }
 
-    public static function setupBeforeClass(): void
+    public static function setUpBeforeClass(): void
     {
         foreach (get_declared_classes() as $class) {
             if ('C' === $class[0] && 0 === strpos($class, 'ComposerAutoloaderInit')) {