Document new `#[expect]` attribute and `reasons` parameter (RFC 2383) #1801

	name: CI
	on:
	pull_request:
	merge_group:

	jobs:
	test:
	name: Test
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@master
	- name: Update rustup
	run: rustup self update
	- name: Install Rust
	run: \|
	rustup set profile minimal
	rustup toolchain install nightly -c rust-docs
	rustup default nightly
	- name: Install mdbook
	run: \|
	mkdir bin
	curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.14/mdbook-v0.4.14-x86_64-unknown-linux-gnu.tar.gz \| tar -xz --directory=bin
	echo "$(pwd)/bin" >> $GITHUB_PATH
	- name: Report versions
	run: \|
	rustup --version
	rustc -Vv
	mdbook --version
	- name: Run tests
	run: mdbook test
	- name: Style checks
	run: (cd style-check && cargo run -- ../src)
	- name: Check for broken links
	run: \|
	curl -sSLo linkcheck.sh \
	https://raw.githubusercontent.com/rust-lang/rust/master/src/tools/linkchecker/linkcheck.sh
	sh linkcheck.sh --all reference

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