README.md: State that the experimental SPDX3 support is write-only. #969

	# SPDX-FileCopyrightText: 2023 spdx contributors
	#
	# SPDX-License-Identifier: Apache-2.0

	name: Install and Test

	on:
	push:
	branches:
	- main
	pull_request:
	workflow_dispatch:

	jobs:
	install_and_test:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ ubuntu-latest, macos-latest, windows-latest ]
	python-version: [ "3.8", "3.9", "3.10", "3.11" ]

	steps:
	- uses: actions/checkout@v3
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Installation
	run: \|
	python -m pip install --upgrade pip
	python -m pip install --upgrade setuptools wheel setuptools_scm build
	python -m build -nwx .
	python -m pip install --upgrade ./dist/*.whl
	python -m pip install pytest
	python -m pip install pyshacl
	python -m pip install tzdata
	python -m pip install networkx
	shell: bash
	- name: Run tests
	run: pytest
	- name: Run CLI
	run: pyspdxtools -i ./tests/spdx/data/SPDXJSONExample-v2.3.spdx.json

Provide feedback