update to django 4 #32

	name: Tests

	on:
	push:
	branches:
	- master
	pull_request:
	branches:
	- master

	jobs:
	test:
	runs-on: ubuntu-latest
	strategy:
	fail-fast: true
	matrix:
	python-version: [3.6, 3.7, 3.8, 3.9]
	django-version: [2.2, 3.1]
	services:
	postgres:
	image: postgres:10
	ports:
	- 5432:5432
	options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
	env:
	POSTGRES_USER: postgres
	POSTGRES_PASSWORD: postgres
	POSTGRES_DB: postgres
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -e .[test]
	pip install -r requirements.txt
	pip install "django~=${{ matrix.django-version }}.0"
	- name: Run tests
	env:
	DATABASE_USER: postgres
	DATABASE_PASSWORD: postgres
	DATABASE_HOST: localhost
	DATABASE_NAME: postgres
	run: \|
	coverage run --parallel -m pytest -x
	- name: Upload coverage to Codecov
	uses: codecov/codecov-action@v1
	with:
	fail_ci_if_error: true
	lint_python:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: 3.7
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -e .[test]
	pip install -r requirements.txt
	- name: Run linters
	run: \|
	flake8 oscar_invoices tests sandbox setup.py
	isort -c -q --diff oscar_invoices/ sandbox/ tests/

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