Migrate to Storybook 8 (#7743)
* migrate to storybook 8
* add changeset
* formatting
* test
* pnpm lock
* revert test
* update testing-library
* pass (and improve) failing tests
* add changeset
* add changeset
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Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
