21.9 skip pixel hitPattern filling for ITK

Skip pixel hitPattern filling for ITK, which anyway isn't reliable, due to insufficient bits for the number of potential layers crossed.

Relevant information should instead be added to the DetailedHitInfo.

This changes output for ITK jobs, since the tracksummary hitpattern changes, but this is expected:

INFO     Reading the reference file from location /tmp/nstyles/clean_run_r1_7f1af610-64ff-4ae2-9ff7-13bdd3274839
ERROR    Py:diff-root         INFO  [xAOD::TrackParticleAuxContainer_v3_GSFTrackParticlesAux.hitPattern]: 1 leaves differ
ERROR    Py:diff-root         INFO  [xAOD::TrackParticleAuxContainer_v3_InDetTrackParticlesAux.hitPattern]: 218 leaves differ

This should not change anything for the current ID, since it is protected behind a check on if(!m_ITkGeometry). (Checked with RunTier0Tests.py)

FYI @asalzbur @npetters @lmijovic @goblirsc @nreadiof @hhayward @nova