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

variety: depend on qt5-tools for KDE support.
https://github.com/void-linux/void-packages/pull/45016

Description:
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Not sure if this is the right choice or if we should just put a note in
`INSTALL.msg`. I did a quick look through
`/usr/share/variety/scripts/set_wallpaper` and it seems like most other DEs
include the needed tool for variety to set the wallpaper.

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

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