Refactor build of C++ for pygambit extension. #1130

	name: pygambit Python extension

	on:
	push:
	pull_request:

	jobs:
	linux:
	runs-on: ubuntu-latest
	if: github.event_name != 'pull_request' \|\| github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
	strategy:
	matrix:
	python-version: ['3.8', '3.12']

	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	- name: Set up dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install setuptools cython pytest wheel lxml numpy scipy
	- name: Build source distribution
	run:
	python setup.py sdist
	- name: Build from source distribution
	run: \|
	cd dist
	pip install -v pygambit*.tar.gz
	- name: Run tests
	run: pytest

	windows:
	runs-on: windows-latest
	if: github.event_name != 'pull_request' \|\| github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
	strategy:
	matrix:
	python-version: ['3.12']

	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v5
	with:
	python-version: ${{ matrix.python-version }}
	- name: Set up dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install cython pytest wheel lxml numpy scipy
	- name: Build extension
	run: \|
	python -m pip install -v .
	- name: Run tests
	run: pytest

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