Merge branch '4.4' into 5.4

* 4.4:
  cs fix
  [Messenger] Fix Doctrine transport on MySQL
  [Translator] Fix translator overlapse
  [Yaml] Improve test coverage in DumperTest and ParserTest
  [Mailer] Fix error message in case of an STMP error
  [HttpClient] Fix shared connections not being freed on PHP < 8
  [HttpFoundation] Fix invalid ID not regenerated with native PHP file sessions
  [HttpClient] Fix memory leak when using StreamWrapper
  Bump Symfony version to 4.4.45
  Update VERSION for 4.4.44
  Update CONTRIBUTORS for 4.4.44
  Update CHANGELOG for 4.4.44

Author: nicolas-grekas