Add a new challenge to verify `CStr` #44

	# This workflow is responsible for building and releasing the book.

	name: Build Book
	on:
	workflow_dispatch:
	pull_request:
	branches: [ main ]
	push:
	paths:
	- 'doc/**'
	- '.github/workflows/book.yml'

	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Install mdbook
	run: \|
	cargo install mdbook --version "^0.4" --locked
	echo "${HOME}/.cargo/bin" >> $GITHUB_PATH

	# Removed --locked for now since it is broken due to old proc_macro feature.
	- name: Install linkchecker
	run: cargo install mdbook-linkcheck --version "^0.7"

	- name: Build Documentation
	run: mdbook build doc

	- name: Upload book
	uses: actions/upload-pages-artifact@v3
	with:
	path: book/html
	retention-days: "2"

	deploy:
	needs: build
	runs-on: ubuntu-latest
	if: ${{ github.event_name == 'push' && startsWith('refs/heads/main', github.ref) }}

	# Grant GITHUB_TOKEN the permissions required to make a Pages deployment
	permissions:
	pages: write # to deploy to Pages
	id-token: write # to verify source

	environment:
	name: github-pages
	url: ${{ steps.deployment.outputs.page_url }}

	steps:
	- name: Deploy to GitHub Pages
	id: deployment
	uses: actions/deploy-pages@v4

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