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

onboard: fix SyntaxWarnings and disable tests
https://github.com/void-linux/void-packages/pull/36398

Description:
- A missing % operator was breaking a c-style format string, causing a
    SyntaxWarning to be trown twice at package install time (during
    byte-compilation).
- The tests were failing since they try to run 'killall' before executing
    onboard in xautomation(7), both not being possible in xbps-src.

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

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