Add file entry for alpine #339

	---
	name: Validate rosdistro
	# this is fine since gha runs with yaml 1.2
	on: # yamllint disable-line rule:truthy
	push:
	branches: ['master']
	pull_request:

	permissions:
	contents: read

	jobs:
	checks:
	name: rosdistro / rosdep checks
	runs-on: ubuntu-20.04
	strategy:
	matrix:
	python-version: [3.8]
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Fetch upstream (to enable diff)
	run: \|
	git remote add unittest_upstream_comparison https://github.com/ros/rosdistro.git \
	\|\| git remote set-url unittest_upstream_comparison https://github.com/ros/rosdistro.git
	git fetch --no-tags --depth=1 unittest_upstream_comparison master
	- name: Install Dependencies
	run: \|
	python -m pip install --upgrade pip setuptools wheel
	python -m pip install -r test/requirements.txt
	- name: Run Tests
	run: pytest -s test
	yamllint:
	name: Yaml Linting
	runs-on: ubuntu-20.04
	strategy:
	matrix:
	python-version: [3.8]
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v1
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install Dependencies
	run: \|
	python -m pip install --upgrade pip setuptools wheel
	pip install yamllint
	- name: Run yamllint
	run: yamllint .

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