Hlt2Conf.test_hlt2_check_packed_data_check fails with warnings

Hlt2Conf.test_hlt2_check_packed_data_check fails because of warnings such as

CaloHypoPacker#1                    WARNING Problem with CaloHypo data packing :-
CaloHypoPacker#1                    WARNING   Original CaloHypo key=98 in '/Event/HLT2/LHCb__Converters__Calo__Hypo__v1__fromV2/OutputHypos'
CaloHypoPacker#1                    WARNING {
hypothesis : Photon
lh : -1
position : { 
z :	12752.8
parameters : -352.334, 132.875, 101594
covariance :
[     0.183737   0.0285899     18.3099
     0.0285899    0.185823     215.366
       18.3099     215.366 7.03394e+06 ]
center : -347.98, 138.406
spread :
[      98.7678     34.2858
       34.2858     235.349 ]
 }
 }
CaloHypoPacker#1                    WARNING   Unpacked CaloHypo
CaloHypoPacker#1                    WARNING {
hypothesis : Photon
lh : -1
position : { 
z :	12752.8
parameters : -352.334, 132.875, 101594
covariance :
[     0.183698     0.02859     18.3011
       0.02859    0.185847     215.368
       18.3011     215.368 7.03395e+06 ]
center : -347.98, 138.406
spread :
[      98.7678     34.2838
       34.2838     235.349 ]
 }
 }

They were somehow taking into account in the test validator but in a fragile way that broke after some configuration changes.

#We expect 5 warning messages due to a calo hypo unpacking
#until understood, count them as expected
from Moore.qmtest.exclusions import remove_known_warnings
countErrorLines({"FATAL": 0, "ERROR": 0, "WARNING": 5},
                stdout=remove_known_warnings(stdout))

We need to find the root cause and fix that. In the meantime we could have some more sophisticated way to filter out only these warnings.

/cc @sesen @jonrob