Checkmk Werk 15476: Fix error if only auxiliary tag help is updated via REST API

ID: 15476 Title: Fix error if only auxiliary tag help is updated via REST API Component: REST API Level: 1 Class: Bug fix Version: 2.3.0b1 If you tried to update only the "help" field of auxiliary tags via REST API, an error like "At least one of the following parameters should be provided: {'topic', 'title'}" occurred.