Fix some PLUME HLT2 monitoring histograms

Merge request opened to fix some PLUME HLT2 monitoring histograms. In particular:

• Fix the cross-histograms by requiring they are filled only when a signal is over threshold and not from empty-empty crossing (previous condition basically allowed calib signals to fill these histograms, rendering them useless)
• Remove pedestal histograms as they are not used
• Removed ADC_calib histograms for bb, be and eb since they only make sense for ee (calib signals are by definition sent only in ee bunch crossings)
• Remove any use of requirements of coincidences between a pair of PMTs to fill histograms, as it's outdated (we should not use anymore the concept of coincidence to fill histograms)

This MR should be somewhat transparent, in the sense that it does not change anything else apart from removing a bunch of histograms that are now created but empty and fixing a condition to fill other histograms.

Depends on: lhcb-datapkg/PRConfig!418 (merged), or better, the new file has been added to the TestFileDB so it does not really depend on this unless one wants to use the TestFileDB key for the input file (don't know if it's possible).

@acarbone @avilla