Add abs() support for Quantity. #43

	name: Testing

	on:
	push:
	branches:
	- 'main'
	pull_request:

	jobs:
	build:
	runs-on: ubuntu-22.04
	strategy:
	max-parallel: 1
	matrix:
	python-version: ['3.10']
	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	- name: Build Cyantities
	run: \|
	# Install packages:
	sudo apt update
	sudo apt-get install -y liblapacke-dev build-essential\
	git openssh-client ssh cython3 \
	ninja-build cmake-data \
	cmake-extras extra-cmake-modules \
	wget libboost-all-dev
	python3 -m pip install --user numpy
	# Use modern GCC:
	sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 10
	sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-10 10
	# Python installs:
	python3 -m pip install --upgrade pip
	sudo apt purge python3-setuptools
	python3 -m pip install --user --verbose .
	- name: Build examples
	run: \|
	cd examples/parabola/
	python3 build.py
	cd ../gravity/
	python3 build.py
	cd ../..
	- name: Lint with flake8
	run: \|
	python3 -m pip install flake8
	# stop the build if there are Python syntax errors or undefined names
	flake8 cyantities --count --select=E9,F63,F7,F82 --show-source --statistics
	- name: Test with pytest
	run: \|
	# Install pytest
	python3 -m pip install pytest
	cd testing
	# Run the test suite:
	pytest -s

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