Fix _export_batches docstring to remove incorrect "threshold" reference (#1287)

Author: DanielHashmi

src/agents/tracing/processors.py

@@ -269,8 +269,7 @@ def _run(self):
 
     def _export_batches(self, force: bool = False):
         """Drains the queue and exports in batches. If force=True, export everything.
-        Otherwise, export up to `max_batch_size` repeatedly until the queue is empty or below a
-        certain threshold.
+        Otherwise, export up to `max_batch_size` repeatedly until the queue is completely empty.
         """
         while True:
             items_to_export: list[Span[Any] | Trace] = []