Fix namespace

Author: tvdijen

tests/lib/Controller/DiscoPowerTest.php

@@ -9,7 +9,7 @@
 use SimpleSAML\Error;
 use SimpleSAML\Module\discopower\Controller;
 use SimpleSAML\Session;
-use SimpleSAML\Test\Utils\ClearStateTestCase;
+use SimpleSAML\TestUtils\ClearStateTestCase;
 use SimpleSAML\XHTML\Template;
 use Symfony\Component\HttpFoundation\Request;