Fix fallback demo app template code (#6129)
* Add test
* add changeset
* Add JSON note
* Fix test
* Update gradio/cli/commands/components/_create_utils.py
* Update test/test_gradio_component_cli.py
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Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
