Update dependency wyrihaximus/test-utilities to v8

Author: mammatusphp-renovate-runner[bot]

composer.json

@@ -6,7 +6,7 @@
         "php": "^8.2"
     },
     "require-dev": {
-        "wyrihaximus/test-utilities": "^6.0.10"
+        "wyrihaximus/test-utilities": "^8.4.0"
     },
     "autoload": {
         "psr-4": {