Use bookkeeping instead of TestFileDB
The TestFileDB is only really meant for small samples used in nightlty tests. It rarely has all the files in a production for a given entry, or even doesn't have entries at all for some interesting productions.
We should transition to using the bookkeeping directly, building upon lhcb-datapkg/PRConfig!170 (merged). The documentation at https://lhcbdoc.web.cern.ch/lhcbdoc/moore/master/tutorials/hltefficiencychecker.html needs to be revisited to be less centered on TestFileDB (perhaps not mention it at all), and possibly the scripts need to be adapted.