We have been running just a subset of osbuild unit tests and also not as
a root, so some of them would be skipped.
In addition, the downstream patches were never applied on sources which
were used for unit-testing. Thus if any issue with test was just
backported as a patch, this had no effect on the test result.
Rework how tests are executed by using a dedicated script which will
take care of the installation of test dependencies, preparation of
sources including application of downstream patches and execute all unit
tests.
Rework also the FMF test metadata and test discovery.
Related: rhbz#2174847
Signed-off-by: Tomáš Hozza <thozza@redhat.com>
