Update app.py

app.py

@@ -57,7 +57,7 @@ def respond(
             response += token
             yield response
 
-    except TencentCloudSDKExceptionas err:
+    except TencentCloudSDKException as err:
         raise gr.Error(f"腾讯云SDK异常: {err}")
     except Exception as e:
         raise gr.Error(f"发生错误: {str(e)}")