New review comment by classabbyamp on void-packages repository

https://github.com/void-linux/void-packages/pull/36228#discussion_r830522676

Comment:
```suggestion
+      if (contents.contains("ID=\"void\""))
```
`ID` or `ID_LIKE` would be the proper way to check this, as it should never change, unlike `PRETTY_NAME`. (see also [the os-release spec](https://www.freedesktop.org/software/systemd/man/os-release.html))