update stages.rst and add description for SearchUnusedMemoryStage and RemoveUnsedMemoryStage #22

	name: Python test

	# Controls when the workflow will run
	on:
	# Triggers the workflow on push or pull request events but only for the "master" branch
	push:
	branches: [ "master" ]
	pull_request:
	branches: [ "master" ]

	jobs:
	build:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	python-version: ["3.9", "3.10", "3.11"]

	steps:
	- uses: actions/checkout@v4
	- name: Set up Python ${{ matrix.python-version }}
	uses: actions/setup-python@v4
	with:
	python-version: ${{ matrix.python-version }}
	- name: Display Python version
	run: python -c "import sys; print(sys.version)"
	- name: Install dependencies
	run: \|
	python -m pip install --upgrade pip
	pip install ruff
	pip install -r requirements.txt
	# install the current zigzag-dse
	pip install .
	# - name: Lint with ruff
	# run: \|
	# # stop the build if there are Python syntax errors or undefined names
	# ruff --format=github --select=E9,F63,F7,F82 --target-version=py37 .
	- name: Lint with ruff
	uses: chartboost/ruff-action@v1
	with:
	src: "./zigzag"
	args: --select E9,F63,F7,F82
	- name: Test with pytest
	run: \|
	pip install pytest
	pytest tests/

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