Update dependency phpunit/phpunit to v11.5.50 [SECURITY] (#14)

Author: rinus

composer.json

@@ -26,7 +26,7 @@
   },
   "require-dev": {
     "phpstan/phpstan": "2.1.33",
-    "phpunit/phpunit": "11.5.44",
+    "phpunit/phpunit": "11.5.50",
     "squizlabs/php_codesniffer": "4.0.1",
     "friendsofphp/php-cs-fixer": "3.92.5"
   }