Fix `fill_value=null` zarr v2 to v3 conversion for string dtypes #3156

	name: CI

	on:
	push:
	branches: [ "main" ]
	paths-ignore:
	- 'docs/**'
	pull_request:
	branches: [ "main" ]
	paths-ignore:
	- 'docs/**'
	schedule:
	- cron: "0 0 * * *"

	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	jobs:
	test:
	name: ${{ matrix.environment }}-build
	runs-on: ubuntu-latest
	defaults:
	run:
	shell: bash -l {0}
	strategy:
	fail-fast: false
	matrix:
	environment: [test-py311, test-py312, min-deps, minio]
	steps:
	- uses: actions/checkout@v4
	- uses: prefix-dev/setup-pixi@v0.9.3
	with:
	pixi-version: v0.59.0
	environments: ${{ matrix.environment }}

	- name: List installed libraries
	run: \|
	pixi install --environment ${{ matrix.environment }}
	pixi list --environment ${{ matrix.environment }}

	- name: Running Tests
	run: \|
	pixi run -e ${{ matrix.environment }} run-tests-xml-cov

	- name: Upload code coverage to Codecov
	uses: codecov/codecov-action@v5.5.1
	with:
	file: ./coverage.xml
	flags: unittests
	env_vars: OS,PYTHON
	name: codecov-umbrella
	fail_ci_if_error: false
	token: ${{ secrets.CODECOV_TOKEN }}

	check-docs:
	name: check-docs
	runs-on: ubuntu-latest
	defaults:
	run:
	shell: bash -l {0}
	steps:
	- uses: actions/checkout@v4
	- uses: prefix-dev/setup-pixi@v0.9.3
	with:
	pixi-version: v0.59.0

	- name: List installed libraries
	run: \|
	pixi install --environment docs
	pixi list --environment docs

	- name: Check documentation build for warnings
	run: \|
	pixi run -e docs check-docs

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