Fix: use set port variable to open browser

Author: Habu-Kagumba

bin/www

@@ -30,7 +30,7 @@ server.listen(port);
 server.on('error', onError);
 server.on('listening', onListening);
 (async () => {
-  await open('http://localhost:3000');
+  await open(`http://localhost:${port}`);
 })();
 
 /**