Documentation for PHPUnit is out of date

[interrupt-routine]

Page at https://docs.codewars.com/languages/php/phpunit

According to https://github.com/codewars/content-issues/wiki/List-of-PHP-Kata-to-Update, from code runner version PHP 8.0 on, the solution should now start with the tag <?php ;and the tests should have:

<?php

use PHPUnit\Framework\TestCase;

class Test {
// ...