Add PHP 8.3 and bump actions/checkout #35

	name: JSON Serializer CI

	permissions:
	contents: read

	on:
	push:
	pull_request:

	jobs:
	testsuite:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	php-version: ['7.0', '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3']
	name: PHP ${{ matrix.php-version }}
	steps:
	- uses: actions/checkout@v4
	- name: Validate composer.json and composer.lock
	run: composer validate
	- name: Cache Composer packages
	id: composer-cache
	uses: actions/cache@v3
	with:
	path: vendor
	key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
	restore-keys: \|
	${{ runner.os }}-php-
	- name: Install suggested dependencies
	run: composer require jeremeamia/superclosure opis/closure
	- name: Install dependencies
	if: steps.composer-cache.outputs.cache-hit != 'true'
	run: composer install --prefer-dist --no-progress --no-suggest
	- name: Run test suite
	run: vendor/bin/phpunit

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