fixing the tox error

Author: Vinothini Dharmaraj

sdk/communication/azure-communication-callautomation/azure/communication/callautomation/_call_connection_client.py

@@ -569,7 +569,7 @@ def start_recognizing_media(
         interrupt_prompt: bool = False,
         dtmf_inter_tone_timeout: Optional[int] = None,
         dtmf_max_tones_to_collect: Optional[int] = None,
-        dtmf_stop_tones: Optional[List[Union[str, DtmfTone]]] = None,
+        dtmf_stop_tones: Optional[List[Union[str, 'DtmfTone']]] = None,
         speech_language: Optional[str] = None,
         choices: Optional[List['RecognitionChoice']] = None,
         end_silence_timeout: Optional[int] = None,

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

@@ -573,7 +573,7 @@ async def start_recognizing_media(
         interrupt_prompt: bool = False,
         dtmf_inter_tone_timeout: Optional[int] = None,
         dtmf_max_tones_to_collect: Optional[int] = None,
-        dtmf_stop_tones: Optional[List[Union[str, DtmfTone]]] = None,
+        dtmf_stop_tones: Optional[List[Union[str, 'DtmfTone']]] = None,
         speech_language: Optional[str] = None,
         choices: Optional[List['RecognitionChoice']] = None,
         end_silence_timeout: Optional[int] = None,