AP for Lb2LcPPbarPi Run2 MC (supersedes !1639)

This is the AP for MC production for Lb -> Lc pbar p pi simulation. This MR supersedes !1639 (merged) The MCDecayTree descriptor is fixed.

Instructions

When creating your merge request:

• Add a label for your WG
• Mark as "Draft:" until you're happy with the CI results
• If the merge request supersedes a previous one, add a comment at the end of the header: (supersedes !<MR number>). Please state explicitly in the description if the superseded ntuples can be deleted immediately, or after the new merge request is finalised

When ready:

• Remove the "Draft:" from the title:
• Assign the merge request to you working group's DPA/RTA liaison

To find your working group's DPA/RTA liaison, see this page:

https://twiki.cern.ch/twiki/bin/viewauth/LHCbPhysics/LHCbWGLiaisons