Clippy Book Chapter Updates Reborn: Type Checking
This PR adds a new chapter to the book: "Type Checking", it hasn't changed a lot from the source mainly because there wasn't many reviews on it and I haven't see a lot of things that needed a change.
## Notes
- I have some doubts about the whole "`is_*` Usage" section, what do you think about it.
- For discussion about the whole project, please use the tracking issue for the project #10597 (It also contains a timeline, discussions, and more information)
changelog: Add a new "Type Checking" chapter to the book
r? `@flip1995`
82d71b1b3a