Merge branch '4.3' into 4.4

* 4.3:
  [FWBundle] Remove unused parameter
  [Intl] [Workflow] fixes English grammar typos
  [Filesystem] [Serializer] fixes English grammar typo
  [Messenger] Adding exception to amqp transport in case amqp ext is not installed
  [Monolog Bridge] Fixed accessing static property as non static.
  Improve Symfony description
  Add DateTimeZoneNormalizer into Dependency Injection
  [Messenger] Error when specified default bus is not among the configured
  [Validator] Add Japanese translation
  [Workflow] Apply the same logic of precedence between the apply() and the buildTransitionBlockerList() method
  Remove some unused methods parameters
  Avoid empty \"If-Modified-Since\" header in validation request
  [Security] Fix SwitchUser is broken when the User Provider always returns a valid user
  Fix error message according to the new regex
  compatibility with DoctrineBundle 2
  [Validator] ConstraintValidatorTestCase: add missing return value to mocked validate method calls

Author: Robin Chalas

Tests/FilesystemTest.php

@@ -797,7 +797,7 @@ public function testSymlink()
         $file = $this->workspace.\DIRECTORY_SEPARATOR.'file';
         $link = $this->workspace.\DIRECTORY_SEPARATOR.'link';
 
-        // $file does not exists right now: creating "broken" links is a wanted feature
+        // $file does not exist right now: creating "broken" links is a wanted feature
         $this->filesystem->symlink($file, $link);
 
         $this->assertTrue(is_link($link));