Auto merge of #53662 - kennytm:rollup, r=kennytm

Rollup of 16 pull requests

Successful merges:

 - #53311 (Window Mutex: Document that we properly initialize the SRWLock)
 - #53503 (Discourage overuse of mem::forget)
 - #53545 (Fix #50865: ICE on impl-trait returning functions reaching private items)
 - #53559 (add macro check for lint)
 - #53562 (Lament the invincibility of the Turbofish)
 - #53563 (use String::new() instead of String::from(""), "".to_string(), "".to_owned() or "".into())
 - #53592 (docs: minor stylistic changes to str/string docs)
 - #53594 (Update RELEASES.md to include clippy-preview)
 - #53600 (Fix a grammatical mistake in "expected generic arguments" errors)
 - #53614 (update nomicon and book)
 - #53617 (tidy: Stop requiring a license header)
 - #53618 (Add missing fmt examples)
 - #53636 (Prefer `.nth(n)` over `.skip(n).next()`.)
 - #53644 (Use SmallVec for SmallCStr)
 - #53664 (Remove unnecessary closure in rustc_mir/build/mod.rs)
 - #53666 (Added rustc_codegen_llvm to compiler documentation.)