Update composer.json

Author: bueltge

composer.json

@@ -37,7 +37,7 @@
         "squizlabs/php_codesniffer": "^3",
         "inpsyde/php-coding-standards": "^1",
         "brain/monkey": "^2.2",
-        "phpunit/phpunit": "^8.5.52",
+        "phpunit/phpunit": "^12.5.22",
         "johnpbloch/wordpress-core": " ^5.0",
         "woocommerce/woocommerce": "^6.6.0"
     },