Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /var/www/html/lib/php-spreadsheet/tests/PhpSpreadsheetTests/Worksheet/IteratorTest.php:10 Stack trace: #0 {main} thrown in /var/www/html/lib/php-spreadsheet/tests/PhpSpreadsheetTests/Worksheet/IteratorTest.php on line 10