build(deps): update friendsofphp/php-cs-fixer requirement in /tools

Updates the requirements on [friendsofphp/php-cs-fixer](https://github.com/PHP-CS-Fixer/PHP-CS-Fixer) to permit the latest version.
- [Release notes](https://github.com/PHP-CS-Fixer/PHP-CS-Fixer/releases)
- [Changelog](https://github.com/PHP-CS-Fixer/PHP-CS-Fixer/blob/master/CHANGELOG.md)
- [Commits](PHP-CS-Fixer/PHP-CS-Fixer@v3.67.0...v3.68.0)

---
updated-dependencies:
- dependency-name: friendsofphp/php-cs-fixer
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

tools/composer.json

@@ -1,6 +1,6 @@
 {
     "require": {
-      "friendsofphp/php-cs-fixer": "^3.67",
+      "friendsofphp/php-cs-fixer": "^3.68",
       "phpstan/extension-installer": "^1.4",
       "phpstan/phpstan": "^1.12",
       "phpstan/phpstan-phpunit": "^1.4",