Require PHPUnit as explicit dependency

Author: jdreesen

composer.json

@@ -22,6 +22,7 @@
     "php": "~8.1.0 || ~8.2.0",
     "doctrine/annotations": "^1.5",
     "doctrine/persistence": "^2.1 || ^3.0",
+    "phpunit/phpunit": "^9.6.0",
     "pimcore/pimcore": "^10.5 || ~11.0.0 || ~11.1.0",
     "psr/log": "^1.0 || ^2.0 || ^3.0",
     "symfony/console": "^5.4 || ^6.2",
@@ -38,8 +39,7 @@
     "phpstan/extension-installer": "^1.3.1",
     "phpstan/phpstan": "^1.10.60",
     "phpstan/phpstan-phpunit": "^1.3.16",
-    "phpstan/phpstan-symfony": "^1.3.8",
-    "phpunit/phpunit": "^9.6.17"
+    "phpstan/phpstan-symfony": "^1.3.8"
   },
   "suggest": {
     "pimcore/admin-ui-classic-bundle": "Required when used with Pimcore 11"