update xpaw/php-source-query-class to v6

Author: Boy132

player-counter/plugin.json

@@ -16,6 +16,6 @@
     "panel_version": null,
     "composer_packages": {
         "xpaw/php-minecraft-query": "^5.0.0",
-        "xpaw/php-source-query-class": "^5.0.0"
+        "xpaw/php-source-query-class": "^6.0.0"
     }
-}
+}