Remove `check-cfg` when Rust 1.80 is released

[BD103]

-Zcheck-cfg has been stabilized-ish! (rust-lang/cargo#13571) When Rust 1.80 is released, the separate Github Action job can be removed.

For now, we have two more releases (12 weeks or ~4 months) before this can be done. 💤

bevy/.github/workflows/ci.yml

Lines 438 to 462 in 4f9f987

	check-cfg:
	runs-on: ubuntu-latest
	timeout-minutes: 30
	steps:
	- uses: actions/checkout@v4
	- uses: actions/cache@v4
	with:
	path: |
	~/.cargo/bin/
	~/.cargo/registry/index/
	~/.cargo/registry/cache/
	~/.cargo/git/db/
	target/
	key: ${{ runner.os }}-check-doc-${{ hashFiles('**/Cargo.toml') }}
	- uses: dtolnay/rust-toolchain@master
	with:
	toolchain: ${{ env.NIGHTLY_TOOLCHAIN }}
	- name: Install Linux dependencies
	uses: ./.github/actions/install-linux-deps
	with:
	wayland: true
	xkb: true
	- name: Build and check cfg typos
	# See tools/ci/src/main.rs for the commands this runs
	run: cargo run -p ci -- cfg-check