fix minimum version of immutable #50

	name: CI

	on: [push]

	jobs:
	phpunit:
	runs-on: ${{ matrix.os }}
	strategy:
	matrix:
	os: [ubuntu-latest, macOS-latest]
	php-version: ['8.1', '8.2', '8.3']
	dependencies: ['lowest', 'highest']
	name: 'PHPUnit'
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php-version }}
	extensions: mbstring, intl
	coverage: xdebug
	- name: Composer
	uses: "ramsey/composer-install@v2"
	with:
	dependency-versions: ${{ matrix.dependencies }}
	- name: PHPUnit
	run: vendor/bin/phpunit --coverage-clover=coverage.clover
	- uses: codecov/codecov-action@v1
	with:
	token: ${{ secrets.CODECOV_TOKEN }}
	psalm:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	php-version: ['8.1', '8.2', '8.3']
	dependencies: ['lowest', 'highest']
	name: 'Psalm'
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php-version }}
	extensions: mbstring, intl
	- name: Composer
	uses: "ramsey/composer-install@v2"
	with:
	dependency-versions: ${{ matrix.dependencies }}
	- name: Psalm
	run: vendor/bin/psalm --shepherd
	cs:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	php-version: ['8.1']
	name: 'CS'
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php-version }}
	extensions: mbstring, intl
	- name: Composer
	uses: "ramsey/composer-install@v2"
	- name: CS
	run: vendor/bin/php-cs-fixer fix --diff --dry-run

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