[RTA/DPA BW Tests] 'Aggressive' Sprucing compression settings in BWTests

Part of lhcb-datapkg/PRConfig#19 (closed), needed by Moore!3795 (closed)

Compression settings to be configurable via options (thus Gaudirun) rather than only in Options (i.e. lbexec)

ToDo:

• Sign off from someone relevant/ more involved with PyConf
• Test via ci-test now redirected to master with Moore!3795 (closed) and lhcb-datapkg/PRConfig!446 (merged)