Add `playback_position` to gr.Audio and gr.Video, which can be updated and read (#12504)
* changes
* chages
* add changeset
* changes
* cxhanges
* changes
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Co-authored-by: Ali Abid <aliabid94@gmail.com>
Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Freddy Boulton <41651716+freddyaboulton@users.noreply.github.com>