MRG: add usage docs for `sig import/ingest` #4137

	name: "Dev env instructions"
	on:
	pull_request:
	push:
	branches: [latest]
	jobs:
	nix:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- uses: cachix/install-nix-action@v23
	with:
	extra_nix_config: \|
	access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}

	- uses: cachix/cachix-action@v12
	with:
	name: sourmash-bio
	authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'

	- run: nix run .# -- --version

	- run: nix-shell --command "tox -e py310"

	mamba:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- name: cache conda
	uses: actions/cache@v3
	env:
	CACHE_NUMBER: 0
	with:
	path: ~/conda_pkgs_dir
	key:
	${{ runner.os }}-conda-${{ env.CACHE_NUMBER }}-${{ hashFiles('environment.yml') }}

	- name: setup conda
	uses: conda-incubator/setup-miniconda@3b0f2504dd76ef23b6d31f291f4913fb60ab5ff3
	with:
	auto-update-conda: true
	python-version: 3.9
	channels: conda-forge,bioconda
	miniforge-variant: Mambaforge
	miniforge-version: latest
	use-mamba: true
	mamba-version: "*"
	activate-environment: sourmash_dev
	auto-activate-base: false
	use-only-tar-bz2: true

	- name: install dependencies
	shell: bash -l {0}
	run: mamba install 'tox>=3.27,<4' tox-conda rust git compilers pandoc

	- name: run tests for 3.9
	shell: bash -l {0}
	run: tox -e py39

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