composer(deps): bump friendsofphp/php-cs-fixer from 2.18.2 to 2.18.6

Bumps [friendsofphp/php-cs-fixer](https://github.com/FriendsOfPHP/PHP-CS-Fixer) from 2.18.2 to 2.18.6.
- [Release notes](https://github.com/FriendsOfPHP/PHP-CS-Fixer/releases)
- [Changelog](https://github.com/FriendsOfPHP/PHP-CS-Fixer/blob/2.18/CHANGELOG.md)
- [Commits](PHP-CS-Fixer/PHP-CS-Fixer@v2.18.2...v2.18.6)

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -13,7 +13,7 @@
   "require": {
     "php": "^7.2 || ^8.0",
     "ext-filter": "*",
-    "friendsofphp/php-cs-fixer": "~2.18.2"
+    "friendsofphp/php-cs-fixer": "~2.18.6"
   },
   "require-dev": {
     "ergebnis/composer-normalize": "^2.13.3",