add temporary docker cleanup cron #2851

	---
	name: CI
	'on':
	pull_request:
	push:
	branches:
	- master

	defaults:
	run:
	working-directory: 'infrastructure-playbook'

	jobs:
	lint:
	name: Lint
	runs-on: ubuntu-latest
	steps:
	- name: Check out the codebase.
	uses: actions/checkout@v2
	with:
	path: 'infrastructure-playbook'

	- name: Set up Python 3.
	uses: actions/setup-python@v2
	with:
	python-version: '3.x'

	- name: Install test dependencies.
	run: pip3 install yamllint

	- name: Lint code.
	run: \|
	yamllint .

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