Show empty JSON icon when value is null

[hannahblair]

Description

We previously showed the Empty state even if we weren't actually rendering the JSON node.

Now, if the value is undefined or an empty string, the JSON component will not render.
If the JSON value is null, the Empty state will show. (Previously, if it was null, it would show the text "null").

Closes: #5845

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[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/a0bd3974ae94aa52f52487fdcf2e6f9dacca2f01/gradio-3.48.0-py3-none-any.whl

Install Gradio Python Client from this PR

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[gradio-pr-bot]

🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/atoms	patch
@gradio/json	patch
gradio	patch

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With the following changelog entry.

Show empty JSON icon when value is null

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[pngwn]

Looks good! Thanks for taking care of this @hannahblair!

wrong

[pngwn]

Looks good! Thanks @hannahblair!