Introduce a new osbuild-tests command and ship it in the -tests
sub-package.
The intended usecase is to install the -tests subpackage into an
otherwise pristine VM, and call the osbuild-tests binary over ssh
from the outside of the booted VM. If the binary exits with a return
code of 0, the tests passed, otherwise they failed. The VM should
not be reused after running the tests.
Signed-off-by: Tom Gundersen <teg@jklm.no>
