Checkmk Werk 13619: Fix crash due to dashboard's ill configured with software inventory object restriction

ID: 13619 Title: Fix crash due to dashboard's ill configured with software inventory object restriction Component: Multisite Level: 1 Class: Bug fix Version: 2.2.0i1 If you configured a dashboard with the object restriction "show information of a single software package", that setting produced a misconfiguration of the dashboard specification. When updating to checkmk 2.1 your site is unusable and you can only see a crash report with the message: TypeError ('NoneType' object is not iterable) This werk fixes the crash, yet we still recommend to remove dashboards that use that restriction.