fix typo : StdClass should be stdClass

Signed-off-by: Abdul Malik Ikhsan <samsonasik@gmail.com>
diff --git a/tests/mocks/ci_testcase.php b/tests/mocks/ci_testcase.php
index f164929..ad4fe5a 100644
--- a/tests/mocks/ci_testcase.php
+++ b/tests/mocks/ci_testcase.php
@@ -27,7 +27,7 @@
 	public function __construct()
 	{
 		parent::__construct();
-		$this->ci_instance = new StdClass();
+		$this->ci_instance = new stdClass();
 	}
 
 	// --------------------------------------------------------------------