Test on 3.12, drop support for 3.7 #185

	name: Test TaskGraph
	on:
	push:
	branches:
	- "**"
	pull_request:
	branches:
	- "**"
	jobs:
	Test:
	runs-on: ${{ matrix.os }}
	strategy:
	fail-fast: false
	matrix:
	python-version: [3.8, 3.9, "3.10", "3.11", "3.12"]
	os: [ubuntu-latest, windows-latest, macos-latest]

	steps:
	- uses: actions/checkout@v2
	with:
	# Fetch all history (it's a small repo) for scm-based versioning
	fetch-depth: 0

	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}

	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	# See this comment about the importlib_metadata constraint:
	# https://github.com/python/importlib_metadata/issues/406#issuecomment-1264666048
	pip install tox tox-gh-actions flake8 "importlib_metadata<5" rstcheck

	- name: Lint with flake8
	run: \|
	# stop the build if there are Python syntax errors or undefined names
	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
	# exit-zero treats all errors as warnings
	flake8 . --count --exit-zero --max-line-length=80 --statistics

	- name: Run tests
	run: \|
	tox

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