Fix up and re-enable tests #158

	# Built from:
	# https://docs.github.com/en/actions/guides/building-and-testing-python
	# https://github.com/snok/install-poetry#workflows-and-tips

	name: Build and test

	on:
	push:
	branches: [ main ]
	pull_request:
	branches: [ main ]

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Set up Python
	uses: actions/setup-python@v5
	with:
	python-version: '3.12'
	- name: Install dependencies
	run: \|
	pip install tox
	- name: Check code quality with flake8
	run: tox -e flake8

	test:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: [ '3.9', '3.10', '3.11', '3.12' ]

	steps:
	- uses: actions/checkout@v4

	- uses: ts-graphviz/setup-graphviz@v2

	- name: Install Poetry
	run: pipx install poetry

	- uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	cache: 'poetry'

	- name: Install dependencies
	run: poetry install

	- name: Run test suite
	run: make test

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