PowhegControl: fix Main31 parameters in some example joboptions (top processes) - AGENE-2047
requested to merge atlas-physics/pmg/mcexperts/powheg-experts/athena:21.6-PowhegControl-FixExampleJOs-Main31Params into 21.6
This MR specifies the Powheg:NFinal main31 parameter for some of the top processes, in the example joboptions. Otherwise it seems Pythia8 crashes in release 22 (not in release 21).
Reminder: the purpose of these example jopboptions is to be used as test, so we should be able to run with them, but other parameters may need to be adjusted for an actual MC sample for physics.