[backend][nodejs] Return random choice from server

backend/nodejs/app.js

@@ -5,7 +5,7 @@ const port = 3000;
 const server = http.createServer((request, response) => {
     response.statusCode = 200;
     response.setHeader('Content-Type', 'text/plain');
-    response.end('Hello World');
+    response.end(randomDecision.getRandomChoice().toString());
 });
 
 server.listen(port, () => {