docs: remove outdated `APP_ENVIRONMENT` variable (#2013) #109

	name: Deploy book
	on:
	push:
	paths: ["docs/book/**"]
	branches:
	- main

	jobs:
	deploy:
	runs-on: ubuntu-latest
	permissions:
	contents: write # To push a branch
	pull-requests: write # To create a PR from that branch
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- name: Install mdbook
	run: \|
	mkdir mdbook
	curl -sSL https://github.com/rust-lang/mdBook/releases/download/v0.4.27/mdbook-v0.4.27-x86_64-unknown-linux-gnu.tar.gz \| tar -xz --directory=./mdbook
	echo `pwd`/mdbook >> $GITHUB_PATH
	- name: Deploy GitHub Pages
	run: \|
	cd docs/book
	mdbook build
	git worktree add gh-pages
	git config user.name "Deploy book from CI"
	git config user.email ""
	cd gh-pages
	# Delete the ref to avoid keeping history.
	git update-ref -d refs/heads/gh-pages
	rm -rf *
	mv ../book/* .
	git add .
	git commit -m "Deploy book $GITHUB_SHA to gh-pages"
	git push --force --set-upstream origin gh-pages

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