[ENH] do not add subject to layout if it is empty #683

	---
	name: 'matlab: tests'

	on:
	push:
	branches:
	- master
	- dev
	pull_request:
	branches: ['*']

	# Allows you to run this workflow manually from the Actions tab
	workflow_dispatch:

	jobs:
	test:


	strategy:
	fail-fast: false
	matrix:
	version: [R2021a, R2021b, R2022a, R2022b]
	os: [ubuntu-latest, macos-latest, windows-latest]

	runs-on: ${{matrix.os}}

	steps:
	- name: Install MATLAB
	uses: matlab-actions/setup-matlab@v1.2.4
	with:
	release: ${{matrix.version}}

	- name: Clone bids-matlab
	uses: actions/checkout@v3
	with:
	submodules: true
	fetch-depth: 1

	- name: Install dependencies
	if: matrix.os == 'ubuntu-latest'
	run: \|
	sudo apt-get -y -qq update
	sudo apt-get -y install unzip wget

	- name: Install bids validator
	run: npm install -g bids-validator

	- name: Install bids example
	run: \|
	cd tests
	make data

	- name: Install Moxunit and MOcov
	run: \|
	git clone https://github.com/MOxUnit/MOxUnit.git --depth 1
	git clone https://github.com/MOcov/MOcov.git --depth 1

	- name: Run commands
	uses: matlab-actions/run-command@v1.1.3
	with:
	command: run MOxUnit/MOxUnit/moxunit_set_path(); addpath(fullfile(pwd, 'MOcov', 'MOcov')); addpath(getenv('GITHUB_WORKSPACE')); success = run_tests();
	assert(success);

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