Remove demo queue concurrency limit

Eliminate the concurrency limit parameter from the demo queue in the main function to simplify the launch process.

app.py

@@ -525,9 +525,6 @@ def main():
             inputs=[],
             outputs=[title_markdown, preset_character_dropdown, preset_voice_dropdown],
         )
-        demo.queue(
-            default_concurrency_limit=concurrency_limit,
-        )
 
     demo.launch()