refac: modernize type annotations (PEP 604 / PEP 585)

backend/open_webui/retrieval/web/external.py

@@ -1,14 +1,11 @@
 import logging
-from typing import Optional, List
+from typing import List, Optional
 
 import requests
-
 from fastapi import Request
-
-
+from open_webui.env import FORWARD_SESSION_INFO_HEADER_CHAT_ID
 from open_webui.retrieval.web.main import SearchResult, get_filtered_results
 from open_webui.utils.headers import include_user_info_headers
-from open_webui.env import FORWARD_SESSION_INFO_HEADER_CHAT_ID
 
 log = logging.getLogger(__name__)