added plaground endpoint configuration

src/playgroud.ts

@@ -1,11 +1,12 @@
 import express from "express";
 import { expressHandler } from "trpc-playground/handlers/express";
 import { AppRouter } from "./app";
+import { Config } from "./config";
 
 export const runPlayground = async (appRouter: AppRouter) => {
   const app = express();
 
-  const trpcApiEndpoint = "http://localhost:3000";
+  const trpcApiEndpoint = Config.api_url;
   const playgroundEndpoint = "/";
 
   app.use(