chore: add missing docstrings in document store base tests #6306

	# If you change this name also do it in linting-skipper.yml and ci_metrics.yml
	name: Linting

	on:
	pull_request:
	paths:
	- "haystack/*/.py"
	- "test/*/.py"
	- "e2e/*/.py"
	- "pyproject.toml"
	- "!haystack/core/*/.py"

	env:
	PYTHON_VERSION: "3.8"
	HATCH_VERSION: "1.9.3"

	jobs:
	mypy:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	# With the default value of 1, there are corner cases where tj-actions/changed-files
	# fails with a `no merge base` error
	fetch-depth: 0

	- name: Get changed files
	id: files
	uses: tj-actions/changed-files@v44
	with:
	files: \|
	*/.py
	files_ignore: \|
	test/**

	- uses: actions/setup-python@v5
	with:
	python-version: "${{ env.PYTHON_VERSION }}"

	- name: Install Hatch
	run: pip install hatch==${{ env.HATCH_VERSION }}

	- name: Mypy
	if: steps.files.outputs.any_changed == 'true'
	run: \|
	mkdir .mypy_cache
	hatch run test:types ${{ steps.files.outputs.all_changed_files }}

	pylint:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4
	with:
	# With the default value of 1, there are corner cases where tj-actions/changed-files
	# fails with a `no merge base` error
	fetch-depth: 0

	- name: Get changed files
	id: files
	uses: tj-actions/changed-files@v44
	with:
	files: \|
	haystack/*/.py

	- uses: actions/setup-python@v5
	with:
	python-version: "${{ env.PYTHON_VERSION }}"

	- name: Install Hatch
	run: pip install hatch==${{ env.HATCH_VERSION }}

	- name: Pylint
	if: steps.files.outputs.any_changed == 'true'
	run: \|
	hatch run test:lint ${{ steps.files.outputs.all_changed_files }}

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