refactor(nc-lib-gui): remove unnecessary line breaks and add comments

packages/nc-lib-gui/lib/XcLibGui.js

@@ -1,19 +1,14 @@
 const express = require('express');
 const path = require('path');
 
-
 class XcLibGui {
-
   static expressMiddleware(dashboardPath) {
-
     const router = express.Router();
-    // Express will serve up production assets i.e. main.js
+    // express will serve up production assets i.e. main.js
+    // dist will be generated from the build in `nc-gui`. See `build:copy` command in `nc-gui`.
     router.use(dashboardPath, express.static(path.join(__dirname, 'dist')));
-
     return router;
   }
 }
 
-module.exports = XcLibGui;
-
-
+module.exports = XcLibGui;