Arm, Field, FieldPat, GenericParam, Param, StructField and Variant

Resolve attributes in several places

Resolve attributes for Arm, Field, FieldPat, GenericParam, Param, StructField and Variant.

This PR is based on @petrochenkov work located at petrochenkov@83fdb8d.

… r=scottmcm

Override `StepBy::{try_fold, try_rfold}`

Previous PR: rust-lang#51435

The previous PR was closed in favor of rust-lang#51601, which was later reverted. I don't think these implementations will make it harder to specialize `StepBy<Range<_>>` later, so we should be able to land this without any consequences.

This should fix rust-lang#57517 – in my benchmarks `iter` and `iter.step_by(1)` now perform equally well, provided internal iteration is used.

check git in bootstrap.py

Fix typo in config.toml.example

…andling, r=Mark-Simulacrum

Unify escape usage

Fixes rust-lang#63443.

I chose to keep the search text when pressing escape so when we focus on the search bar, we got the results again without needing to load them again. I also unified a bit a few things (maybe I should have done it in another commit, sorry...).

r? @Mark-Simulacrum