[ATR-20060] Run 3 trigger configuration updates for legacy TrigVal transform, but with a Run 3 AOD as input

This builds on !24869 (merged) - and hence it cherry-picks the commits from that MR.

The new changes of this MR are those in PhysicsAnalysis/PATJobTransforms/share/skeleton.PhysicsValidation_tf.py and the additions to the ART tests.

Some temporary glue is added to help interface legacy monitoring/validation code with the MT trigger output.

EDMDecodingVersion is set to 3 in the versions of the test which run the MT trigger in master.