Design: Link to content from MTTL

When I click on a link on a training link on the MTTL I'd like to be brought to the most relevant and appropriate material possible. There are multiple examples of "appropriate" content:

1. For organic in house training with material available the content might be slides/mdbook.
2. For externally procured courses might be a sign up page (or perhaps website with information?)
3. For training without content available we might bring them to simply a signup page (e.g. Classified training in person).

Right now it seems like the links drop me into a repo instead. This might be confusing for beginners who won't know how to access MDbook and/or slide content from a repo. One reason is we don't include links to the slides and/or mdbooks in all cases.

Acceptance Criteria:

• Design proposal for changes to support the above options