virt-what uses "which", but doesn't have a Requires: for it.

Around several corners, that can result in "funny" things like salt reporting a
VM as "grains[virtual]: physical" instead of the expected "kvm".
If you are interested in the full story, have a look at
https://progress.opensuse.org/issues/62204 (especially comment 5) - it's long,
but quite entertaining ;-)

Wild guess: virt-what has Requires: util-linux, but according to which.changes,
which was split off into its own package in January 2013.

Please
- add "Requires: which" to virt-what.spec
- submit it to Tumbleweed
- submit a maintenance update to Leap 15.x

I'm not sure if Requires: util-linux is still needed - but I'm afraid you'll
have to check the whole script to check that. If in doubt, just keep it -
looking at the commands it ships, it's probably impossible to have a system
without it ;-)