chore(deps): update dependency drupol/php-conventions to v6

Author: renovate[bot]

composer.json

@@ -30,7 +30,7 @@
     },
     "require-dev": {
         "ext-pcov": "*",
-        "drupol/php-conventions": "^5",
+        "drupol/php-conventions": "^6",
         "friends-of-phpspec/phpspec-code-coverage": "^6",
         "infection/infection": ">= 0.26",
         "infection/phpspec-adapter": "^0.2",