rustfmt no longer builds after rust-lang/rust#74653

[rust-highfive]

Hello, this is your friendly neighborhood mergebot.
After merging PR #74653, I observed that the tool rustfmt no longer builds.
A follow-up PR to the repository https://github.com/rust-lang/rustfmt is needed to fix the fallout.

cc @petrochenkov, do you think you would have time to do the follow-up work?
If so, that would be great!

And nominating for compiler team prioritization.

[calebcartwright]

A bump of the rustc-ap crates in rustfmt is required to address this.

• (1) bump rustc-ap* in racer and publish new version on crates.io (bump rustc-ap to v671 racer-rust/racer#1124)
• (1) bump rustc-ap* on rustfmt 1.x branch and publish new version on crates.io (merged, crates.io publish pending but rls can use branch in rustfmt repo rustfmt 1.x bump rustc-ap to v671 rustfmt#4356)
• (2) update racer and rustfmt references in rls
• (3) update rustfmt and rls submods in rust-lang/rust repo (merge pending Update RLS and Rustfmt #75427)

Note that the rustc-ap bumps in racer and rustfmt can be done in parallel, the remaining tasks have to be sequenced

[branan]

Are there additional issues/complications that are blocking this? I bumped rustfmt/racer locally and rls seems to build - I'd be happy to open PRs if that's all it takes to get this green again

[calebcartwright]

It's my understanding that @Xanewok is already working on step 2 (updating the references in rls). I can't really speak to what's going on in rls, which branch is planned/whether there's other commits to be included/etc. You may want to ask directly in rust-lang/rls or on #74811