Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\londoncityroom\vendor\rubix\ml\tests\Tokenizers\WordStemmerTest.php:13 Stack trace: #0 {main} thrown in C:\xampp\htdocs\londoncityroom\vendor\rubix\ml\tests\Tokenizers\WordStemmerTest.php on line 13