lint: Test and improve PNG transparency check (f-019) #2274

	name: Standard Ebooks toolset tests

	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-22.04

	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v4
	with:
	python-version: '3.x'
	- name: Install Ubuntu packages
	run: \|
	sudo apt update
	sudo apt install calibre default-jre git python3-venv
	- name: Install pipx packages
	run: \|
	pipx install .
	pipx inject standardebooks pytest==8.2.2 pylint==3.2.2 mypy==1.10.0 types-requests==2.32.0.20240602 types-setuptools==70.0.0.20240524 types-Pillow==10.2.0.20240520
	- name: Check type annotations with mypy
	run: $PIPX_HOME/venvs/standardebooks/bin/mypy
	- name: Check code with pylint
	run: $PIPX_HOME/venvs/standardebooks/bin/pylint tests/*.py se
	- name: Test with pytest
	run: $PIPX_HOME/venvs/standardebooks/bin/pytest

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