Update version to 8.4.0 #319

	# 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]
	php: ['7.4', '8.0']

	services:
	mysql:
	image: mysql:5.6
	env:
	MYSQL_ALLOW_EMPTY_PASSWORD: false
	MYSQL_ROOT_PASSWORD: password
	MYSQL_DATABASE: test
	ports:
	- 3306/tcp
	options: --health-cmd="mysqladmin ping" --health-interval=10s --health-timeout=5s --health-retries=3

	steps:
	- name: Checkout
	uses: actions/checkout@v4

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

	- name: Start mysql service
	run: sudo /etc/init.d/mysql start

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

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

	- name: Unit Tests
	run: composer ci:tests:unit

	- name: Functional Tests
	env:
	typo3DatabaseName: test
	typo3DatabaseUsername: root
	typo3DatabasePassword: password
	typo3DatabaseHost: 127.0.0.1
	typo3DatabasePort: ${{ job.services.mysql.ports['3306'] }}
	run: \|
	composer ci:tests:functional

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