Update TestBase.php

Trying to fix Error from Scrutinizer:
PHP Fatal error:  Call to a member function get() on a non-object in /home/scrutinizer/build/package/Tests/TestBase.php on line 60  
https://scrutinizer-ci.com/g/codeconsortium/CCDNUserSecurityBundle/inspections/d4678526-3c3f-4ba8-9de4-a01b168bbdfc