Bump black from 23.3.0 to 23.7.0 in /tests #89

	name: Building and testing
	on: [push]
	jobs:
	building:
	runs-on: ubuntu-latest
	container:
	image: alexpovel/latex
	# Need root, otherwise this exact issue occurs:
	# https://github.community/t/permission-problems-when-checking-out-code-as-part-of-github-action/202263
	options: --user root
	steps:
	- name: Checkout repository
	uses: actions/checkout@v3
	- name: Run preflight checks
	run: make preflight
	- name: Build all LaTeX PDFs
	run: make tex
	- name: Build README PDF
	run: make README.pdf
	- name: Archive compilation artifacts
	uses: actions/upload-artifact@v3
	with:
	name: pdfs
	path: ./*.pdf
	if-no-files-found: error
	testing:
	needs: building
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v3
	with:
	python-version: "3.10"
	- uses: snok/install-poetry@v1
	with:
	virtualenvs-create: false
	- name: Install Python dependencies
	working-directory: ./tests # Needs to find pyproject.toml file
	run: poetry install
	- name: Test the suite itself
	run: make test-self
	- uses: actions/download-artifact@v3
	with:
	name: pdfs # Specify name, else it'll be downloaded to a subdirectory
	- name: Test generated PDFs
	run: make test-pdfs

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