add test + demo

[pngwn]

Description

cc @aliabid94

Includes demo + functional test for #8515. I've updated that issue to explain what I think is going on. It doesnb't seem super consistent though, so you may have a better insight.

Closes: #8515

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/0d15ed42ca7f02a0ab1e8469d57edf2a87f29145/gradio-4.36.1-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@0d15ed42ca7f02a0ab1e8469d57edf2a87f29145#subdirectory=client/python"

Install Gradio JS Client from this PR

npm install https://gradio-builds.s3.amazonaws.com/0d15ed42ca7f02a0ab1e8469d57edf2a87f29145/gradio-client-1.1.1.tgz

[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
gradio	patch

• [ ] Maintainers can select this checkbox to manually select packages to update.

With the following changelog entry.

add test + demo

Maintainers or the PR author can modify the PR title to modify this entry.

#### Something isn't right?

- Maintainers can change the version label to modify the version bump. - If the bot has failed to detect any changes, or if this pull request needs to update multiple packages to different versions or requires a more comprehensive changelog entry, maintainers can [update the changelog file directly](https://github.com/gradio-app/gradio/edit/8515-apifalse-queue/.changeset/lemon-planets-kiss.md).