feat: remove unnecessary logger from test app

The logger middleware was moved to the `morgan` package in newer versions of express.

tests/apps/dockerfile-dokku-scale/web.js

@@ -1,6 +1,6 @@
 var express = require('express');
 
-var app = express.createServer(express.logger());
+var app = express();
 
 app.get('/', function(request, response) {
   response.send('nodejs/express');