update phpunit

Author: mtmail

composer.json

@@ -18,7 +18,7 @@
     "php": ">=8.1"
   },
   "require-dev": {
-    "phpunit/phpunit": "^10.5 || ^11.0 || ^12.0",
+    "phpunit/phpunit": "^12.5.8",
     "squizlabs/php_codesniffer": "^3.7 || ^4.0",
     "phpstan/phpstan": "^2.0" 
   },