Add hlt2+sprucing bandwidth test on pp+SMOG simulation
Add test infrastructure for pp+pAr MC (SMOG worst case scenario in terms of bandwidth/rate, see details in !411 (closed)). As this is also tested as a qmt test on 100 events in Moore, giving conflicts as pp and pp+SMOG2 tests run in parallel and write to tmp, an OVERRIDE_BASEDIR argument is used, to have the pp+SMOG2 test writing on tmp_SMOG2 rather than tmp. This modification is only used for the qmt, as the bandwidth test runs on one machine only (and tmp is cleaned up in between). In this way, no modification is required to the PRHandler.
To be tested with !428 (merged)
Also related to lhcb-core/LHCbNightlyConf!1231 (merged)
Supersedes (well, includes) !411 (closed) To be tested with lhcb/Moore!3563 (merged) and also related to lhcb-core/LHCbNightlyConf!1231 (merged)
Closes https://gitlab.cern.ch/lhcb-dpa/project/-/issues/295
cc @oboenteg @kmattiol and many thanks to @rjhunter and @lugrazet for the help in troubleshooting