Merge branch '6.4' into 7.0

* 6.4:
  [FrameworkBundle] fixes #54402: Suppress PHP warning when is_readable() tries to access dirs outside of open_basedir restrictions
  return null when message with name is not set
  use local PHP web server to test HTTP stream wrappers
  [Translation] Silence error when intl not loaded
  Bump Symfony version to 6.4.7
  Update VERSION for 6.4.6
  Update CHANGELOG for 6.4.6
  Bump Symfony version to 5.4.39
  Update VERSION for 5.4.38
  Update CONTRIBUTORS for 5.4.38
  Update CHANGELOG for 5.4.38

Author: xabbuh

Command/CacheClearCommand.php

@@ -200,7 +200,7 @@ private function isNfs(string $dir): bool
 
         if (null === $mounts) {
             $mounts = [];
-            if ('/' === \DIRECTORY_SEPARATOR && is_readable('/proc/mounts') && $files = @file('/proc/mounts')) {
+            if ('/' === \DIRECTORY_SEPARATOR && @is_readable('/proc/mounts') && $files = @file('/proc/mounts')) {
                 foreach ($files as $mount) {
                     $mount = \array_slice(explode(' ', $mount), 1, -3);
                     if (!\in_array(array_pop($mount), ['vboxsf', 'nfs'])) {