Fix abnormal user invitaion message. (#4081)

### What problem does this PR solve?

### Type of change

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

api/apps/tenant_app.py

@@ -62,8 +62,10 @@ def create(tenant_id):
     user_id = usrs[0].id
     user_tenants = UserTenantService.query(user_id=user_id, tenant_id=tenant_id)
     if user_tenants:
-        if user_tenants[0].status == UserTenantRole.NORMAL.value:
+        if user_tenants[0].role == UserTenantRole.NORMAL:
             return get_data_error_result(message="This user is in the team already.")
+        if user_tenants[0].role == UserTenantRole.OWNER:
+            return get_data_error_result(message="This user is the owner of the team.")
         return get_data_error_result(message="Invitation notification is sent.")
 
     UserTenantService.save(