Use ruff for linting and formatting. #1075

	name: test

	on:
	push: # any branch
	pull_request:
	branches: [master]

	jobs:
	test-ubuntu:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: [3.7, 3.8, 3.9, "3.10", "3.11"]

	steps:
	- uses: actions/checkout@v2
	- name: Setup Python ${{ matrix.python-version }}
	uses: actions/setup-python@v2
	with:
	python-version: ${{ matrix.python-version }}
	- name: Install Dependencies
	run: \|
	sudo apt remove python3-pip
	python -m pip install --upgrade pip
	python -m pip install . ruff coverage codecov mypy pytest readme_renderer types-contextvars asyncssh
	pip list
	- name: Ruff
	run: \|
	ruff .
	ruff format --check .
	- name: Tests
	run: \|
	coverage run -m pytest
	- name: Mypy
	# Check wheather the imports were sorted correctly.
	# When this fails, please run ./tools/sort-imports.sh
	run: \|
	mypy --strict src/prompt_toolkit --platform win32
	mypy --strict src/prompt_toolkit --platform linux
	mypy --strict src/prompt_toolkit --platform darwin
	- name: Validate README.md
	# Ensure that the README renders correctly (required for uploading to PyPI).
	run: \|
	python -m readme_renderer README.rst > /dev/null
	- name: Run codecov
	run: \|
	codecov

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