Revert black version for older Python runtimes #894

	# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
	name: CI Build

	on:
	push:
	branches: [ main ]
	pull_request:

	jobs:
	build:
	# Avoiding -latest due to https://github.com/actions/setup-python/issues/162
	runs-on: ubuntu-20.04
	timeout-minutes: 10
	strategy:
	matrix:
	python-version: ['3.6', '3.7', '3.8', '3.9', '3.10', '3.11']
	env:
	PYTHON_SLACK_SDK_MOCK_SERVER_MODE: 'threading'
	CI_LARGE_SOCKET_MODE_PAYLOAD_TESTING_DISABLED: '1'
	steps:
	- uses: actions/checkout@v3
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install dependencies
	run: \|
	pip install -U pip wheel
	pip install -e ".[testing]"
	pip install -e ".[optional]"
	- name: Run validation
	run: \|
	python setup.py validate
	- name: Run tests for SQLAlchemy v1.4 (backward-compatibility)
	run: \|
	# Install v1.4 for testing
	pip install "SQLAlchemy>=1.4,<2"
	python setup.py unit_tests --test-target tests/slack_sdk/oauth/installation_store/test_sqlalchemy.py && \
	python setup.py unit_tests --test-target tests/slack_sdk/oauth/state_store/test_sqlalchemy.py
	- name: Run codecov (only 3.9)
	if: startsWith(matrix.python-version, '3.9')
	uses: codecov/codecov-action@v3
	with:
	token: ${{ secrets.CODECOV_TOKEN }}
	# python setup.py validate generates the coverage file
	files: ./coverage.xml

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