Include _custom_build in sdist #260

	name: Docs

	on: [push, pull_request]

	jobs:
	docs:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- name: Set up Python 3.8
	uses: actions/setup-python@v4
	with:
	python-version: 3.8
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install -r requirements.txt
	- name: Build pycapnp and install
	run: \|
	python setup.py build
	pip install .
	- name: Build documentation
	run: \|
	sphinx-build docs build/html

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