Use pipx in actions to install poetry; fix docs build #5

	---
	name: Auto-deployment of pid4cat_model documentation
	on:
	push:
	branches: [main]
	workflow_dispatch:

	jobs:
	build-docs:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	with:
	fetch-depth: 0 # otherwise, you will failed to push refs to dest repo

	- name: Set up Python
	uses: actions/setup-python@v4
	with:
	python-version: 3.9

	- name: Install Poetry
	run: pipx install poetry

	- name: Install dependencies.
	run: poetry install -E docs

	- name: Build documentation.
	run: \|
	mkdir -p docs
	touch docs/.nojekyll
	make gendoc
	([ ! -f docs/about.md ] && cp src/docs/about.md docs/) \|\| true
	make mkd-gh-deploy

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