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

herbstluftwm: update to 0.9.4.
https://github.com/void-linux/void-packages/pull/36301

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

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#### New package
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#### Local build testing
- I built this PR locally for my native architecture, (x86_64-glibc)