Add back unpacking counters in test_davinci_tupling_array_taggers / test_davinci-issue-97_bkgcat_mc-truth

Add back the check of the unpacking counters in:

https://gitlab.cern.ch/lhcb/DaVinci/-/blob/2024-patches/DaVinciExamples/tests/qmtest/tupling.qms/test_davinci_tupling_array_taggers.qmt?ref_type=heads

https://gitlab.cern.ch/lhcb/DaVinci/-/blob/2024-patches/DaVinciTests/tests/qmtest/mc.qms/test_davinci-issue-97_bkgcat_mc-truth.qmt?ref_type=heads

These were turned off whilst waiting for a move to the new Gaudi with this fix in: gaudi/Gaudi!1617 (merged)

See related issues/MRS: #216 (closed), #215 (closed)