Use `main` branch for CI badges #241

	name: Python linter (Darker)

	on: [pull_request]
	jobs:
	darker:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout code
	uses: actions/checkout@v2
	with:
	fetch-depth: 0

	- name: Set up Python
	uses: actions/setup-python@v5
	with:
	python-version: '3.10'

	- name: Install pip dependencies
	run: python -m pip install darker[isort] flake8 flake8-quotes isort --quiet

	# use `--ignore=F821` to avoid raising false positive error in typing
	# annotations with string, e.g. def my_method(my_model: 'ModelName')

	# darker still exit with code 1 even with no errors on changes
	- name: Run Darker with base commit
	run: \|
	output=$(darker --check --isort -L "flake8 --max-line-length=88 --ignore=F821" kpi kobo hub -r ${{ github.event.pull_request.base.sha }})
	[[ -n "$output" ]] && echo "$output" && exit 1 \|\| exit 0
	shell: /usr/bin/bash {0}

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