Update dependency drupol/php-conventions to v6

Author: renovate[bot]

composer.json

@@ -22,7 +22,7 @@
         "symfony/console": "^4 || ^5 || ^6"
     },
     "require-dev": {
-        "drupol/php-conventions": "^1.6.14",
+        "drupol/php-conventions": "^6.0.0",
         "friends-of-phpspec/phpspec-code-coverage": "^6.0.0",
         "infection/infection": "^0.13.6 || ^0.15.3 || ^0.26.0",
         "microsoft/tolerant-php-parser": "^0.1.0",