Revert "Lock NPM versions."

This reverts commit b544af14e4.

backend/src/index.ts

@@ -1,5 +1,6 @@
 import { Express, Request, Response, NextFunction } from 'express';
 import * as express from 'express';
+import * as compression from 'compression';
 import * as http from 'http';
 import * as https from 'https';
 import * as WebSocket from 'ws';
@@ -65,6 +66,7 @@ class Server {
         res.setHeader('Access-Control-Allow-Origin', '*');
         next();
       })
+      .use(compression())
       .use(express.urlencoded({ extended: true }))
       .use(express.json());