Add Gesture Recognition example

[andreasnaoum]

Use the MediaPipe Gesture detection and Gesture landmark detection solutions to track hands and recognise gestures in images and videos.

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  • Using newly built examples: app.rerun.io
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  • Using full set of examples from nightly build: app.rerun.io
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[emilk]

I pushed some fixes - make sure you pull them down with git pull. There are some mypy issues still in there.

[abey79]

I didn't look thoroughly at the actual code, but it generally seems inline with our past examples and I could successfully run it locally without any issue 👍🏻