Add docs archive checkout. #307

	name: docs
	on:
	push:
	branches:
	- main
	- feature/docs_fix
	- feature/new_docs
	jobs:
	build:
	runs-on: ubuntu-22.04
	strategy:
	matrix:
	python: [ 3.9.5 ]
	steps:
	- name: install pandoc
	run: \|
	sudo apt-get install pandoc
	sudo apt-get install --reinstall python3-pkg-resources
	- uses: actions/setup-python@v2
	- uses: actions/checkout@v2
	with:
	ref: ${{ github.ref }}
	fetch-depth: 0 # otherwise, you will failed to push refs to dest repo
	- name: Build and Commit
	uses: sphinx-notes/pages@v2
	with:
	documentation_path: docs/source
	requirements_path: docs/docs-requirements.txt
	- name: checkout v0.3.x archive
	run: \|
	mkdir ./v0.3.x
	cd ./v0.3.x
	git submodule add https://github.com/databrickslabs/mosaic.git v0.3.x/mosaic
	git checkout gh-pages-v0.3.x
	git add --all
	cd ./mosaic
	git add --all
	git commit -am "Adding v0.3.x docs"
	ls -la
	- name: Push changes
	uses: ad-m/github-push-action@master
	with:
	github_token: ${{ secrets.GITHUB_TOKEN }}
	branch: gh-pages

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