Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\wamp64\www\wp-content\plugins\elementskit\libs\composer\vendor\paragonie\constant_time_encoding\tests\Base64Test.php:4 Stack trace: #0 {main} thrown in C:\wamp64\www\wp-content\plugins\elementskit\libs\composer\vendor\paragonie\constant_time_encoding\tests\Base64Test.php on line 4