xAOD::EventInfo conversion fix in PileUpEventLoopMgr (ATLASSIM-4081)

This MR fixes missing beamspot and pile-up info when converting EventInfo to xAOD::EventInfo in PileUpEventLoopMgr.

Attaching overlay diff-root for reference: diff-root-overlay-d1498.RDO.log

/cc @amorley @jchapman