Checkmk Werk 7966: Web API: Fix broken set_hosttags API call

ID: 7966 Title: Web API: Fix broken set_hosttags API call Component: WATO Level: 1 Class: Bug fix Version: 1.7.0i1 The API call for updating the tag configuration did not work in previous 1.6 releases. Calls did always fail with an error like this: "AttributeError: 'Rule' object has no attribute 'tag_specs'\n".