fix(composer): remove phpunit/phpunit from require-dev

... and hope require will install phpunit-12

Author: rtm-ctrlz

composer.json

@@ -24,8 +24,7 @@
   },
   "require-dev": {
     "squizlabs/php_codesniffer": "^3.9.0",
-    "phpstan/phpstan": "^2.1.3",
-    "phpunit/phpunit": "^12.0"
+    "phpstan/phpstan": "^2.1.3"
   },
   "autoload-dev": {
     "psr-4": {