Introduce tox for testing #468

	name: Build and Test
	on:
	push:
	branches:
	- '*'
	pull_request:
	paths:
	- '*'

	jobs:
	sdist:
	name: Build distribution
	runs-on: ubuntu-latest
	steps:
	- name: Checkout Repository
	uses: actions/checkout@v2
	- name: Set up Python
	uses: actions/setup-python@v1
	with:
	python-version: '3.x'
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip3 install --break-system-packages setuptools wheel twine
	- name: Build distribution
	run: python3 setup.py sdist
	test:
	name: Run mock unit tests
	runs-on: ubuntu-latest
	container: precice/precice:nightly
	steps:
	- name: Checkout Repository
	uses: actions/checkout@v2
	- name: Install FEniCS and tox
	run: \|
	apt update
	apt install -y software-properties-common
	add-apt-repository ppa:fenics-packages/fenics -y
	apt update
	apt install -y fenics tox
	- name: Run unit tests
	run: tox -e unit
	- name: Run integration tests
	run: tox -e integration

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