### What problem does this PR solve?

Fixed  #5839
This PR fix  error code 102, stating dataset_ids is required.

curl --request POST \
     --url http://{address}/api/v1/chats \
     --header 'Content-Type: application/json' \
     --header 'Authorization: Bearer <YOUR_API_KEY>' \
     --data '{
         "name": "test_chat"
     }'
     
     this is not getting datasetids , fix for it. 

file location : sdk\python\ragflow_sdk\ragflow.py

added : "dataset_ids": dataset_list if dataset_list else [],



### Type of change

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

Co-authored-by: Raghav <2020csb1115@iitrpr.ac.in>