Add py.typed marker file for mypy #266

	name: Tests

	on:
	push:
	pull_request:
	branches:
	- main

	jobs:
	build:
	runs-on: ubuntu-20.04

	steps:
	- uses: actions/checkout@v3

	# Use GitHub's Docker registry to cache intermediate layers
	- run: echo ${{ secrets.GITHUB_TOKEN }} \| docker login docker.pkg.github.com -u $GITHUB_ACTOR --password-stdin
	- run: docker pull docker.pkg.github.com/$GITHUB_REPOSITORY/aleph-message-build-cache \|\| true

	- name: Build the Docker image
	run: \|
	git fetch --prune --unshallow --tags
	docker build . -t aleph-message:${GITHUB_REF##*/} -f Dockerfile --cache-from=docker.pkg.github.com/$GITHUB_REPOSITORY/aleph-message-build-cache

	- name: Cache the image on GitHub's repository
	run: docker tag aleph-message:${GITHUB_REF##*/} docker.pkg.github.com/$GITHUB_REPOSITORY/aleph-message-build-cache && docker push docker.pkg.github.com/$GITHUB_REPOSITORY/aleph-message-build-cache \|\| true

	- name: Test with black in the Docker image
	run: \|
	docker run aleph-message:${GITHUB_REF##*/} black --check aleph_message

	- name: Test with ruff in the Docker image
	run: \|
	docker run aleph-message:${GITHUB_REF##*/} ruff aleph_message

	- name: Pytest in the Docker image
	run: \|
	docker run aleph-message:${GITHUB_REF##*/} pytest -vv --cov aleph_message

	- name: MyPy in the Docker image
	run: \|
	docker run aleph-message:${GITHUB_REF##*/} mypy aleph_message --install-types --non-interactive --check-untyped-defs --ignore-missing-imports

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