Update Dockerfile

Dockerfile

@@ -3,7 +3,7 @@ RUN mkdir -p /app
 RUN apt install nodejs npm
 RUN npm install express nodejs
 
-COPY COPY <<EOF /app/index.js
+COPY <<EOF /app/index.js
 const express = require("express");
 const app = express();
 const { createProxyMiddleware } = require("http-proxy-middleware");