Checkmk Werk 8852: Fix error on tag management page when tags are defined outside of WATO

ID: 8852 Title: Fix error on tag management page when tags are defined outside of WATO Component: WATO Level: 1 Class: Bug fix Version: 1.7.0i1 When tags were added to the configuration using the wato_host_tags variable outside of WATO while the WATO configuration was already based on the 1.6 format, this resulted in an exception on the tag management page which has now been fixed.