fix deprecation #4

	name: CI

	on:
	push:
	branches: [ master ]
	pull_request:
	branches: [ master ]

	jobs:
	phpunit:
	name: Tests
	strategy:
	fail-fast: false
	matrix:
	os: [ubuntu-latest]
	php:
	- "7.1"
	- "7.2"
	- "7.3"
	- "7.4"
	- "8.0"
	dependencies:
	- "lowest"
	- "highest"
	symfony-yaml: ['^3.4', '^4', '^5', '^6']
	include:
	- os: "windows-latest"
	php: "8.0"
	dependencies: "highest"
	symfony-yaml: '5.4.2'
	- os: "macos-latest"
	php: "8.0"
	dependencies: "highest"
	symfony-yaml: '^5'
	exclude:
	# symfony/yaml v5 does not run on PHP 7.1
	- php: '7.1'
	symfony-yaml: '^5'
	# symfony/yaml v6 does not run on PHP 7.*
	- php: '7.1'
	symfony-yaml: '^6'
	- php: '7.2'
	symfony-yaml: '^6'
	- php: '7.3'
	symfony-yaml: '^6'
	- php: '7.4'
	symfony-yaml: '^6'
	# symfony/yaml v3.4 is not compatible with PHP 8.0 but has no upper-bound, so it installs on it
	- php: '8.0'
	symfony-yaml: '^3.4'

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

	steps:
	- uses: actions/checkout@v2

	- name: Install PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	coverage: pcov
	tools: composer:v2

	- name: Require specific symfony/yaml version
	run: "composer require symfony/yaml:'${{ matrix.symfony-yaml }}' --prefer-dist --no-interaction --ansi --no-install"

	- name: "Install dependencies with Composer"
	uses: "ramsey/composer-install@v2"
	with:
	dependency-versions: "${{ matrix.dependencies }}"

	- name: Validate test data
	run: make lint

	- name: PHPUnit tests
	run: make test

	- name: Code coverage
	run: make coverage

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