doc: mention return value for group.run() methods #653

	name: CI
	on: [push, pull_request]
	jobs:
	lint:
	runs-on: ubuntu-20.04
	name: lint
	steps:
	- uses: actions/checkout@master
	- uses: actions/setup-python@v4
	with:
	python-version: "3.11"
	- run: pip install tox
	- run: tox -e lint

	build-unix:
	timeout-minutes: 30
	strategy:
	fail-fast: false
	matrix:
	os: ["ubuntu-20.04"]
	python: ["3.7", "3.8", "3.9", "3.10", "3.11"]
	concurrency: ["cpython", "gevent"]

	runs-on: ${{ matrix.os }}
	name: test on ${{ matrix.python }} (${{ matrix.os }}, ${{ matrix.concurrency }})

	services:
	memcached:
	image: memcached:latest
	ports:
	- 11211:11211
	rabbitmq:
	image: bitnami/rabbitmq:latest
	env:
	RABBITMQ_USERNAME: "dramatiq"
	RABBITMQ_PASSWORD: "dramatiq"
	ports:
	- 5672:5672
	options: '--hostname "rmq" --health-cmd "rabbitmqctl status" --health-interval 10s --health-timeout 10s --health-retries 3 --health-start-period 60s'
	redis:
	image: redis:latest
	ports:
	- 6379:6379

	steps:
	- uses: actions/checkout@master
	- uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python }}
	- run: \|
	sudo apt-get update
	sudo apt-get remove libhashkit2 libmemcached11 \|\| true
	sudo apt-get install -y libmemcached-dev
	- run: pip install -e '.[dev]'
	- run: pytest --benchmark-skip
	if: ${{ matrix.concurrency == 'cpython' }}
	env:
	RABBITMQ_USERNAME: "dramatiq"
	RABBITMQ_PASSWORD: "dramatiq"
	- run: python pytest-gevent.py --benchmark-skip
	if: ${{ matrix.concurrency == 'gevent' }}
	env:
	RABBITMQ_USERNAME: "dramatiq"
	RABBITMQ_PASSWORD: "dramatiq"

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