Fix stopping chat interface when stop button is clicked (#9626)
* changes
* add changeset
* changes
* changes
* fix test
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Co-authored-by: Ali Abid <aliabid94@gmail.com>
Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
