test: create fake etc/apt/preferences.d to silence test warnings #180

	name: CI

	on: [push, pull_request]

	jobs:
	tests:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: static checks
	run: \|
	sudo apt update
	sudo apt build-dep -y ./
	sudo apt install -y python3-pytest
	pytest-3
	# ensure running each test standalone works
	for f in test/test_*.py; do
	if [ "$(basename $f)" = "test_base.py" ]; then
	continue
	fi
	pytest-3 $f
	done
	- name: setup
	run: \|
	sudo apt-get update
	sudo apt-get install distro-info autopkgtest git-buildpackage
	- name: build source
	run: gbp buildpackage -us -uc -S -d -nc --git-ignore-branch --git-prebuild=
	- name: autopkgtest
	# skipping tests is ok, virt-null is used because lxd keeps failing
	# with: "Timed out waiting for container to boot"
	run: sudo autopkgtest -U ../build-area/*.dsc -- null \|\| [ $? == 2 ]

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