fix matrix notation in workflow specs #4

	name: Unit tests (Linux)

	on: [push]

	jobs:
	build:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.9", "3.10", "3.11", "3.12"]
	steps:
	- uses: actions/checkout@v3
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Set up renderer
	run: \|
	sudo apt-get update
	sudo apt-get install -y libgl1-mesa-dev libgl1-mesa-glx libosmesa6-dev
	echo "MUJOCO_GL=egl" >> $GITHUB_ENV
	echo "PYOPENGL_PLATFORM=egl" >> $GITHUB_ENV
	- name: Install dependencies
	run: \|
	sudo apt-get install ffmpeg
	pip install --upgrade pip
	pip cache purge
	pip install "flyvision @ https://github.com/Nely-EPFL/flyvis/archive/refs/heads/main.zip"
	pip install -e ".[dev,examples]"
	- name: Lint with ruff
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	ruff --output-format=github --select=E9,F63,F7,F82 --target-version=py38 .
	- name: Test with pytest
	run: \|
	python -m pytest

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