Tweak AUM test for consistency

In the past it was decided to run AUM test only on Fixed Function images to make a better use of LAVA, following this approach avoid running aum-offline-upgrade-collection_id on HMI.

Also, due to the reduce availability of amd64 hardware AUM tests were disabled for that arch. However, it makes sense to at leas run a very basic set of AUM test to confirm that the functionality works in amd64 arch.

Signed-off-by: Walter Lozano walter.lozano@collabora.com