(MAJOR) Update node from v16 to v20 #208

	# Summary:
	# Test the GitHub Action using an integration test.
	# Makes sure the GitHub Action works properly when running on a clean machine, without building anything (integration test).
	# This integration test will break if the Vercel project or deployment are deleted, or if the VERCEl_TOKEN doesn't have access to the deployment url.
	#
	# See https://github.com/actions/checkout https://github.com/actions/checkout/releases/tag/v3

	name: 'GitHub Action integration test'
	on:
	pull_request:
	push:

	jobs:
	run-integration-test:
	strategy:
	matrix:
	version: [ 16, 18, 20 ]
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- run: yarn # Install all dependencies
	- uses: ./
	env:
	VERCEL_TOKEN: ${{ secrets.VERCEl_TOKEN }}
	with:
	# Testing whether some existing vercel deployment is properly deployed
	deployment-url: "nextjs-bzyss249z.vercel.app" # In our case (at Unly), the "VERCEL_DOMAIN" secret value should probably use the same value
	timeout: 10

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