fix(rustic-babel): disable toolchain when invalid/unneeded #3

	name: CI

	on: [push, pull_request]

	jobs:
	unix-test:
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-latest]
	emacs-version:
	- 27.2
	- 28.1
	steps:
	- uses: actions/checkout@v2

	- uses: purcell/setup-emacs@master
	with:
	version: ${{ matrix.emacs-version }}

	- uses: conao3/setup-cask@master
	with:
	version: 0.8.4

	- name: Install requirements
	run: \|
	echo "$HOME/.cask/bin" >> $GITHUB_PATH
	echo "$HOME/bin" >> $GITHUB_PATH

	sudo apt update
	sudo apt install -y gnutls-bin gnupg2 dirmngr
	sudo apt install -y texinfo libgif-dev libxpm-dev

	- name: Install needed rust stuff
	run: \|
	curl -sSf https://build.travis-ci.com/files/rustup-init.sh \| sh -s -- --default-toolchain=stable -y
	source $HOME/.cargo/env
	rustup component add rustfmt-preview

	- name: rustic-doc prerequisites
	run: \|
	wget https://github.com/jgm/pandoc/releases/download/2.17.0.1/pandoc-2.17.0.1-1-amd64.deb
	sudo dpkg -i pandoc-2.17.0.1-1-amd64.deb
	mkdir -p ~/.local/bin
	mkdir -p ~/.local/share/emacs/rustic-doc/std/
	curl -sL https://github.com/sharkdp/fd/releases/download/v8.3.2/fd-v8.3.2-x86_64-unknown-linux-musl.tar.gz \| tar xz --wildcards --strip-components=1 -C /usr/local/bin '*/fd'
	curl -sL https://github.com/BurntSushi/ripgrep/releases/download/13.0.0/ripgrep-13.0.0-x86_64-unknown-linux-musl.tar.gz \| tar xz --wildcards --strip-components=1 -C /usr/local/bin '*/rg'
	rustup component add rust-docs

	- name: Run tests
	run: \|
	make test

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