deps: update phpunit

Author: ovx

composer.json

@@ -18,7 +18,7 @@
         "ext-json": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "^11.5",
+        "phpunit/phpunit": "^11.5.50",
         "phpstan/phpstan": "^2.1",
         "phpstan/phpstan-phpunit": "^2.0",
         "phpstan/extension-installer": "^1.4",