Update kaesar-* stable tag support #16

	name: CI
	on: [push, pull_request]

	# Explicitly set workflow permissions to avoid additional permissions being added from
	# the Github UI.
	permissions:
	contents: read

	jobs:
	build:
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v3
	with:
	fetch-depth: 2
	- name: Install dependencies
	run: \|
	sudo apt-get install emacs # emacs 26 on ubuntu 20
	sudo apt-get install git jq mercurial texinfo

	# Work around SSL-related failures, see
	# https://stackoverflow.com/questions/21477683/mercurial-https-clone-abort-error-wrong-version-number
	echo -e "[ui]\ntls = False" >> $HOME/.hgrc
	# enable mercurial's purge extension:
	echo -e "[extensions]\npurge =" >> $HOME/.hgrc
	- name: Run CI script
	run: \|
	[ "$GITHUB_EVENT_NAME" = "push" ] \
	&& export CHANGED_FILES=$(git diff-tree --name-only --no-commit-id -r ${{ github.sha }})

	[ "$GITHUB_EVENT_NAME" = "pull_request" ] \
	&& export CHANGED_FILES=$(\
	curl --silent https://api.github.com/repos/"$GITHUB_REPOSITORY"/pulls/${{ github.event.pull_request.number }}/files \
	\| jq -r '.[] \| .filename')

	./.github/workflows/ci.sh

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