Adding script to do throughput testing for FTv6

Adding a new script for throughput testing with FTv6

Things to do so it appears in the PR tests:

• copy input file from mdf:root://eoslhcb.cern.ch//eos/lhcb/grid/prod/lhcb/swtest/lhcb/swtest/Beam7000GeV/Upgrade-MagUp-Nu7.6-25ns-Pythia8/Sim10-Up02/uncompressed_large.mdf to /scratch/lhcbpr2/uncompressed_large.mdf
• wait for LHCbNightlyConf!262 (merged) and put new tests into the relevant database
• wait for Moore!298

@maszyman do you have the powers to help with the first two points?
@sstahl could you check if it all makes sense?