Curriculum & Challenges in getting started does not link to current docs

[majestic-owl448]

The current getting started guide, in the Curriculum & Challenges section points to How to Work on Coding Challenges and Curriculum File Structure, but does not point to the various How to Work on labs/workshops/quizzes/reviews docs that we have. Those instead or in Optional Reading below.

I would propose to update or the coding challenges one to redirect to the various ones after giving the common infos (how to create a project maybe) or update the getting started page to put the other "how to work on" pages in a more prominent position.