Merge branch '5.1' into 5.2

* 5.1:
  µCS fix
  CS fix
  CS fix
  [travis] use PHP 8.0 to patch return types and run deps=low
  Add me as a Notifier code owner
  Update sl_SI translations
  Don't trigger deprecation for deprecated aliases pointing to deprecated definitions
  [HttpFoundation] use atomic writes in MockFileSessionStorage
  Make EmailMessage & SmsMessage transport nullable
  remove unused argument
  [DI] fix param annotation
  [Config] Add \Symfony\Component\Config\Loader::load() return type
  Simplify PHP CS Fixer config
  Rename normalize param

Author: nicolas-grekas

composer.json

@@ -47,7 +47,7 @@
         "symfony/twig-bridge": "^4.4|^5.0",
         "symfony/validator": "^4.4|^5.0",
         "symfony/yaml": "^4.4|^5.0",
-        "twig/twig": "^2.10|^3.0"
+        "twig/twig": "^2.13|^3.0.4"
     },
     "conflict": {
         "symfony/browser-kit": "<4.4",