Add workflow to lint 3rd party repositories #5

	# SPDX-FileCopyrightText: 2023 DB Systel GmbH
	#
	# SPDX-License-Identifier: GPL-3.0-or-later

	# Build reuse-tool and lint 3rd party repositories for which we know that they
	# are reliably REUSE compliant, rather complex, use several annotation
	# strategies, and are quite popular. This shall prevent that we introduce
	# unforeseen and unintended breaking changes.

	name: Lint 3rd party repositories

	on:
	push:
	branches:
	- main
	pull_request:

	jobs:
	third-party-lint:
	runs-on: ubuntu-latest
	continue-on-error: ${{ matrix.ignore-failure }}
	strategy:
	# do not abort the whole test job if one step fails
	fail-fast: false
	#
	matrix:
	repo: ["fsfe/reuse-example", "curl/curl", "SAP/openui5"]
	ignore-failure: [false]
	# add a repo for which we know it's not compliant
	include:
	- repo: spdx/license-list-XML
	ignore-failure: true

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python
	uses: actions/setup-python@v2
	with:
	python-version: 3.8
	- name: Install dependencies
	run: \|
	pip install poetry
	poetry install --no-interaction --no-dev
	# Clone and lint repositories
	- name: Clone ${{ matrix.repo }}
	uses: actions/checkout@v3
	with:
	repository: ${{ matrix.repo }}
	path: 3rd/${{ matrix.repo }}
	- name: Lint ${{ matrix.repo }}
	run: poetry run reuse --root 3rd/${{ matrix.repo }} lint

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