fix KB config reload bug (#213)

### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._


### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

api/db/services/knowledgebase_service.py

         fields = [
             cls.model.id,
             #Tenant.embd_id,
-            cls.embd_id,
+            cls.model.embd_id,
             cls.model.avatar,
             cls.model.name,
             cls.model.language,