There's a merged pull request on the void-packages repository

New package: svt-av1-0.9.1
https://github.com/void-linux/void-packages/pull/35551

Description:
closes https://github.com/void-linux/void-packages/issues/35541

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#### Testing the changes
- I tested the changes in this PR: **YES**

I tested this by encoding a video using `ffmpeg -i in.mp4 -c:v libsvtav1 out.mkv`.

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