Add slevomat/coding-standard to composer.json

Author: DominikWolos

composer.json

@@ -11,7 +11,8 @@
         "phpstan/phpstan-strict-rules": "^0.12.0",
         "phpstan/phpstan-webmozart-assert": "0.12.12",
         "symplify/easy-coding-standard": "^9.4",
-        "friendsofphp/php-cs-fixer": "^3.0"
+        "friendsofphp/php-cs-fixer": "^3.0",
+        "slevomat/coding-standard": "^7.0"
     },
     "autoload": {
         "psr-4": {