cars-assemble: remove links from introduction #1575
Description
The introduction.md document of the cars-assemble exercise contains links to external resources.
As per the docs:
Links should be used sparingly, if at all. While a link explaining a complex topic like recursion might be useful, for most concepts the links will provide more information than needed so explaining things concisely inline should be the aim.
In this case, the links can be removed and use in the concept's about.md document.