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

chroot-grep: update to 3.7.
https://github.com/void-linux/void-packages/pull/38785

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

The regular grep package is 3.7, not sure if there is a specific reason to keep this on 3.3, so feel free to let me know.

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