Check_MK Werk 5981: Fixed displaying of BI aggregation with icons

ID: 5981 Title: Fixed displaying of BI aggregation with icons Component: BI Level: 1 Class: Bug fix Version: 1.6.0i1 When displaying BI aggregations that want to display an icon, for example when a service is in downtime, an exception like this could occur: TypeError: render_icon() got an unexpected keyword argument 'class_'.