dev: allow for psalm 6.0 for 8.4+

Author: drwho725

composer.json

@@ -22,7 +22,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^9",
-        "vimeo/psalm": "^5.0",
+        "vimeo/psalm": "^4.6 || ^5.0 || ^6.0",
         "friendsofphp/php-cs-fixer": "^3.0"
     },
     "autoload": {