qa: fix missing argument to sprintf in assertion message

Signed-off-by: Matthew Weier O'Phinney <matthew@weierophinney.net>

Author: weierophinney

src/Model/InputFilterModel.php

@@ -163,7 +163,10 @@ protected function addInputFilter($module, $controller, $inputFilter, $validator
         $entityType = $this->getEntityType($controller);
         $return     = new $entityType($updated['input_filter_specs'][$validator]);
 
-        assert($return instanceof ArrayAccess, sprintf('Entity of type %s does not implement ArrayAccess'));
+        assert($return instanceof ArrayAccess, sprintf(
+            'Entity of type %s does not implement ArrayAccess',
+            $entityType
+        ));
 
         $return['input_filter_name'] = $validator;
         return $return;