removing operation call back url for continuous dtmf

Author: Vinothini Dharmaraj

sdk/communication/azure-communication-callautomation/azure/communication/callautomation/aio/_call_connection_client_async.py

@@ -718,8 +718,7 @@ async def start_continuous_dtmf_recognition(
         """
         continuous_dtmf_recognition_request = ContinuousDtmfRecognitionRequest(
             target_participant=serialize_identifier(target_participant),
-            operation_context=operation_context,
-            operation_callback_uri=operation_callback_url
+            operation_context=operation_context
         )
         await self._call_media_client.start_continuous_dtmf_recognition(
             self._call_connection_id,