Add a project settting to keep track of map themes' default active layer #330

	name: Continuous integration
	on: push
	jobs:
	code_check:
	name: Code check
	runs-on: ubuntu-latest
	steps:
	- name: Checkout repo
	uses: actions/checkout@v2
	- name: Setup Python
	uses: actions/setup-python@v1
	with:
	python-version: 3.8
	- name: Install pipenv
	run: pip install pipenv
	- name: Check code formatting
	run: \|
	pipenv install pre_commit
	pipenv run python -m pre_commit run --all-files
	test:
	runs-on: ubuntu-20.04
	strategy:
	matrix:
	qgis_version: [release-3_16, release-3_22, release-3_28, final-3_36_1]
	env:
	QGIS_TEST_VERSION: ${{ matrix.qgis_version }}
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	with:
	submodules: recursive
	- name: Test on QGIS LTR 3.
	run: \|
	docker-compose -f .docker/docker-compose.yml run qgis /usr/src/.docker/run-docker-tests.sh
	test_packaging:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v3
	with:
	submodules: recursive
	- name: Setup Python
	uses: actions/setup-python@v4
	with:
	python-version: 3.8
	cache: 'pip'
	- name: Install toolchain
	run: pip install build
	- name: Package with build
	run: python -m build
	- name: Install with pip
	run: pip install .

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