Add tests for TYPO3 12 #39

	# Adapted from https://github.com/TYPO3GmbH/blog/blob/master/.github/workflows/ci.yml
	name: CI

	on: [pull_request]

	jobs:
	build:
	runs-on: ubuntu-latest

	strategy:
	fail-fast: false
	matrix:
	typo3: ['^11.5', '^12.4']
	php: ['8.1']
	include:
	- typo3: ^11.5
	php: '7.4'
	- typo3: ^11.5
	php: '8.0'
	- typo3: ^12.4
	php: '8.2'

	steps:
	- name: Checkout
	uses: actions/checkout@v2

	- name: Setup PHP ${{ matrix.php }}, with composer and extensions
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	extensions: mbstring, dom, zip

	- name: Validate composer.json and composer.lock
	run: composer validate

	- name: Get composer cache directory
	id: composer-cache
	run: echo "::set-output name=dir::$(composer config cache-files-dir)"

	- name: Cache composer dependencies
	uses: actions/cache@v2
	with:
	path: ${{ steps.composer-cache.outputs.dir }}
	key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
	restore-keys: ${{ runner.os }}-composer-

	- name: Install dependencies with typo3/cms-core:${{ matrix.typo3 }}
	run: \|
	composer require typo3/cms-core:${{ matrix.typo3 }} --no-progress
	git checkout composer.json

	- name: php-cs-fixer
	run: composer ci:php:fixer

	- name: Lint PHP
	run: composer ci:php:lint

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