Merge branch '6.4' into 7.0

* 6.4:
  Skip Twig v3.9-dev for now
  [Validator] Update Dutch (nl) translation
  Update Albanian translations
  [Validator] Update translation
  [FrameworkBundle] Prevent silenced warning by checking if /proc/mount exists
  [VarDumper][PhpUnitBridge] Fix color detection
  prevent throwing NOT_FOUND error when tube is empty
  [Validator] Update missing validator translation for Swedish
  [FrameworkBundle] Fix eager-loading of env vars in ConfigBuilderCacheWarmer
  [Messenger] Fix failing Redis test
  [Validator] Update Italian (it) translations
  [Validator] Missing translations for Hungarian (hu) #53769
  revert to native PHP union types
  [Validator] Missing translations for Russian (ru) #53775
  fix syntax errors on PHP 7

Author: nicolas-grekas

composer.json

@@ -50,7 +50,7 @@
         "symfony/twig-bridge": "^6.4|^7.0",
         "symfony/validator": "^6.4|^7.0",
         "symfony/yaml": "^6.4|^7.0",
-        "twig/twig": "^3.0.4",
+        "twig/twig": "~3.8.0",
         "web-token/jwt-checker": "^3.1",
         "web-token/jwt-signature-algorithm-hmac": "^3.1",
         "web-token/jwt-signature-algorithm-ecdsa": "^3.1",