Update github actions for checkout and setup node to v4 #122

	name: Sync to Open CoDE

	concurrency: Sync

	on:
	push:
	branches: [main]

	jobs:
	to_opencode:
	runs-on: ubuntu-latest
	timeout-minutes: 5
	steps: # <-- must use actions/checkout before mirroring!
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: Ensure all branches are available
	run: \|
	git fetch origin -u '+refs/heads/:refs/heads/' --update-head-ok

	- name: Sync repo to OpenCoDE
	shell: bash
	run: \|
	set -x

	# Create ssh client config
	mkdir ~/.ssh
	cat <<EOF > ~/.ssh/config
	Host $DESTINATION_HOST
	ServerAliveInterval 60
	ServerAliveCountMax 5
	KexAlgorithms ecdh-sha2-nistp521
	EOF

	# Add host key
	ssh-keyscan $DESTINATION_HOST > ~/.ssh/known_hosts

	# Start ssh-agent and add private key
	eval $(ssh-agent)
	echo "$SSH_KEY" \| sed '$ s/\n$//' \| ssh-add -

	# List local branches
	git branch --all

	# Push
	git remote add destination git@$DESTINATION_HOST:$DESTINATION_REPO
	git push destination -f --all --prune
	git push destination -f --tags
	env:
	SSH_KEY: ${{ secrets.OPENCODE_SSH_PRIVATE_KEY }}
	DESTINATION_HOST: gitlab.opencode.de
	DESTINATION_REPO: digitalservicebund/digitalservicebund.git

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