🔧(app-desk) trailingSlash options when build

Add trailingSlash options to next.config.js
to be able to reach directly a page without adding
".html" at the end.

src/frontend/apps/desk/next.config.js

@@ -1,6 +1,7 @@
 /** @type {import('next').NextConfig} */
 const nextConfig = {
   output: 'export',
+  trailingSlash: true,
   images: {
     unoptimized: true,
   },