Rollup of 8 pull requests
Successful merges:
- #53218 (Add a implementation of `From` for converting `&'a Option<T>` into `Option<&'a T>`)
- #54024 (Fix compiling some rustc crates to wasm)
- #54095 (Rename all mentions of `nil` to `unit`)
- #54173 (Suggest valid crate type if invalid crate type is found)
- #54194 (Remove println!() statement from HashMap unit test)
- #54203 (Fix the stable release of os_str_str_ref_eq)
- #54207 (re-mark the never docs as unstable)
- #54210 (Update Cargo)
Failed merges:
r? @ghost