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

slock: added line in build section of template to factor in config.h
https://github.com/void-linux/void-packages/pull/37736

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

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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)