Update dependency phpunit/phpunit to v12

Author: renovate[bot]

composer.json

@@ -9,7 +9,7 @@
         "php": "^7.4.0|^8.0"
     },
     "require-dev" : {
-        "phpunit/phpunit": "^9.1.4"
+        "phpunit/phpunit": "^12.0.0"
     },
     "license": "MIT",
     "authors": [