Auto merge of #53870 - Xanewok:update-rls, r=oli-obk
Update RLS and Rustfmt
RLS
* Allow project model to download crates ([#1020](https://github.com/rust-lang-nursery/rls/pull/1020))
* Support simple external builds ([#988](https://github.com/rust-lang-nursery/rls/pull/988))
* Support using external Rustfmt ([#990](https://github.com/rust-lang-nursery/rls/pull/990))
Rustfmt (0.99.4)
* Format chains with comment ([#2899](https://github.com/rust-lang-nursery/rls/pull/2899))
* Do not show wildcard pattern in slice pattern ([#2912](https://github.com/rust-lang-nursery/rls/pull/2912))
* Impl only use ([#2951](https://github.com/rust-lang-nursery/rls/pull/2951))
* ... and [more](https://github.com/rust-lang-nursery/rustfmt/compare/5c9a2b6c13d3b6f8d3f9c02b130bb4b54fd489fb...1c408818c8a752dd584e7858b4afd3ceb011a7da)
Bumped in tandem to pull a single version of `rustc-ap-*` libs.
r? @nrc