Fix deprecation warning: Replace get_events with search_events (#9188)

Co-authored-by: openhands <openhands@all-hands.dev>

openhands/utils/conversation_summary.py

@@ -95,7 +95,7 @@ async def auto_generate_title(
 
         # Find the first user message
         first_user_message = None
-        for event in event_stream.get_events():
+        for event in event_stream.search_events():
             if (
                 event.source == EventSource.USER
                 and isinstance(event, MessageAction)