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

signify: update to 31.
https://github.com/void-linux/void-packages/pull/38590

Description:
Edit: I also added changelog and removed the UPDATE file, which doesn't seem correct anymore.

Add needed libmd makedepend and tar checkdepend,
use vsed instead of sed for the file patching,
and use sed instead of head to extract a nicer LICENSE file

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