🐛(app-desk) add next-env.d.ts

next-env.d.ts lot of types for the next.js.
next.js boilerplate don't version the
next-env.d.ts file, so it was being ignored by git.
This was causing the CI to fail with the ts linter.

src/frontend/apps/desk/.gitignore

@@ -33,4 +33,3 @@ yarn-error.log*
 
 # typescript
 *.tsbuildinfo
-next-env.d.ts