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

common/build-style/python3-pep517: add missing \n for msg_warn
https://github.com/void-linux/void-packages/pull/40426

Description:
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Fixes the following (missing newline) for this warning:
![image](https://user-images.githubusercontent.com/47358222/200971182-8f275696-2d34-424b-af51-de9d0a88262e.png)


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

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