Use `python3` instead of `python` #66

	name: Changelog check

	on:
	# allows us to run workflows manually
	workflow_dispatch:
	pull_request:

	env:
	GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

	jobs:
	changelog_update:
	runs-on: ubuntu-latest
	container:
	image: alpine:3.14

	name: Is Changelog up-to-date ?
	steps:
	- name: Install latest git
	run: \|
	apk add --no-cache bash git openssh
	git --version

	- name: Checkout repository
	uses: actions/checkout@v4

	- run: \|
	git config --global --add safe.directory ${GITHUB_WORKSPACE}
	cd $GITHUB_WORKSPACE
	git remote add cymetric https://github.com/cyclus/cymetric.git
	git fetch cymetric
	change=`git diff cymetric/main -- CHANGELOG.rst \| wc -l`
	git remote remove cymetric
	if [ $change -eq 0 ]; then
	echo "CHANGELOG.rst has not been updated"
	exit 1
	fi

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