Pass phpstan level 1 tests

classes/plugin/Controllers/AbstractController.php

@@ -8,6 +8,7 @@ use Grav\Common\Grav;
 use Grav\Common\Inflector;
 use Grav\Common\Language\Language;
 use Grav\Common\Utils;
+use Grav\Framework\Flex\Interfaces\FlexObjectInterface;
 use Grav\Framework\Form\Interfaces\FormInterface;
 use Grav\Framework\Psr7\Response;
 use Grav\Framework\RequestHandler\Exception\NotFoundException;
@@ -172,6 +173,11 @@ abstract class AbstractController implements RequestHandlerInterface
         return $form;
     }
 
+    /**
+     * @return FlexObjectInterface
+     */
+    abstract public function getObject();
+
     /**
      * Get Grav instance.
      *