Update app.py

https://github.com/gradio-app/gradio/issues/6339
I don't know if this fix alone will work, Gradio is incompatible with some of the options and syntax when versions change.

app.py

@@ -502,6 +502,6 @@ if __name__ == '__main__':
                             ]
                         )
 if limitation is True:
-    app.queue(concurrency_count=1, max_size=20, api_open=config.api).launch(share=config.colab)
+    app.queue(max_size=20, api_open=config.api).launch(share=config.colab)
 else:
-    app.queue(concurrency_count=1, max_size=20, api_open=config.api).launch(share=True)
+    app.queue(max_size=20, api_open=config.api).launch(share=True)