Fix gr.Dataframe's focus for accessibility

[hannahblair]

Description

Please include a concise summary, in clear English, of the changes in this pull request. If it closes an issue, please mention it here.

Closes: #11735

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🦄 change detected

This Pull Request includes changes to the following packages.

Package	Version
@gradio/dataframe	patch
gradio	patch

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• Fix gr.Dataframe's focus for accessibility

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