Added polars dataframe support with demo (#7139)
* first commit
* minor update
* working polars
* fixed. demo added.
* add changeset
* dynamic import of polars
* Fix import logic
* add changeset
* Fix lint
* Add code
* Fix code
* Add code
* remove screenshot'
* delete
* add changeset
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Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: freddyaboulton <alfonsoboulton@gmail.com>
