Rollup merge of rust-lang#114309 - rustbot:docs-update, r=ehuss

Update books

## rust-lang/reference

7 commits in 1ea0178266b3f3f613b0fabdaf16a83961c99cdb..9cd5c5a6ccbd4c07c65ab5c69a53286280308c95
2023-07-29 22:29:51 UTC to 2023-07-16 20:12:46 UTC

- Fix merge queue building twice. (rust-lang/reference#1383)
- Clarify UB around immutability & mutation (rust-lang/reference#1385)
- mention the extra const UB (rust-lang/reference#1273)
- Operator expressions: make the note about division by zero clearer. (rust-lang/reference#1384)
- Make unsafe keyword docs less confusing (rust-lang/reference#1379)
- Say that division by zero for primitive types panics (rust-lang/reference#1382)
- Add CI trigger for merge queues. (rust-lang/reference#1381)

## rust-lang/rust-by-example

3 commits in 8a87926a985ce32ca1fad1be4008ee161a0b91eb..07e0df2f006e59d171c6bf3cafa9d61dbeb520d8
2023-07-24 11:37:55 UTC to 2023-07-24 11:35:36 UTC

- Added attribute unused_labels - fixed warning. (rust-lang/rust-by-example#1729)
- more explanation about panic (rust-lang/rust-by-example#1728)
- chore: add the portuguese version of this project to `readme.md` (rust-lang/rust-by-example#1727)

## rust-lang/rustc-dev-guide

26 commits in b5a12d95e32ae53791cc6ab44417774667ed2ac6..24eebb6df96d037aad285e4f7793bd0393a66878
2023-07-30 11:23:23 UTC to 2023-07-11 06:02:34 UTC

- fix(name-resolution): remove unnecessary closing paranthesis (rust-lang/rustc-dev-guide#1760)
- fix(macro-expansion.md): fix the article `an` to `a` (rust-lang/rustc-dev-guide#1759)
- fix(serialization.md): fix the name of a derive macro (rust-lang/rustc-dev-guide#1756)
- fix(serialization.md): add a necessary plural suffix (rust-lang/rustc-dev-guide#1757)
- fix(salsa.md): add punctuation to prevent confusion (rust-lang/rustc-dev-guide#1754)
- fix(salsa.md): remove duplicate "To Be" verb (rust-lang/rustc-dev-guide#1755)
- feat(fuzzing.md): make `halfempty` word a link (rust-lang/rustc-dev-guide#1750)
- fix(about.md): use `a` instead of `an` (rust-lang/rustc-dev-guide#1751)
- refactor(git.md): make git-scm links clickable (rust-lang/rustc-dev-guide#1747)
- fix(walkthrough.md) add a comma operator to eliminate ambiguity (rust-lang/rustc-dev-guide#1749)
- fix(git.md): remove a confusing end of sentence character (rust-lang/rustc-dev-guide#1748)
- refactor(profiling/with_perf): remove a wrong to be verb (rust-lang/rustc-dev-guide#1746)
- refactor(tests/headers): remove duplicate list item (rust-lang/rustc-dev-guide#1745)
- refactor(test/headers.md): make the meaning more obvious (rust-lang/rustc-dev-guide#1744)
- refactor(tests/ui): remove unnecessary duplicate word (rust-lang/rustc-dev-guide#1743)
- refactor(compiletest): remove unnecessary duplicate word (rust-lang/rustc-dev-guide#1742)
- generic_arguments.md: substs -> GenericArgs (rust-lang/rustc-dev-guide#1741)
- fix(suggested): remove an unnecessary and confusing statement (rust-lang/rustc-dev-guide#1739)
- fix(how-to-build-and-run): fix a typo ("fromer" -> "former") (rust-lang/rustc-dev-guide#1736)
- fix(how-to-build-and-run): remove a wrong paragraph (rust-lang/rustc-dev-guide#1735)
- coverage code has moved (rust-lang/rustc-dev-guide#1728)
- linked issue is closed (rust-lang/rustc-dev-guide#1729)
- remove duplicate reference in about-this-guide.md (rust-lang/rustc-dev-guide#1734)
- Explain more in depth what early and late bound generic parameters are (rust-lang/rustc-dev-guide#1732)
- add section for normalization with the new solver (rust-lang/rustc-dev-guide#1731)
- Improve cleanup-crew.md with an example post (rust-lang/rustc-dev-guide#1730)