release/21.6.64

Ewelina Maria Lobodzinska

@ewelina

582f80b5 · Merge branch 'epos_verbosity' into '21.6' · Mar 24, 2021

contains MRs:
https://gitlab.cern.ch/atlas/athena/-/merge_requests/41944 update to OpenLoops 2.1.2 
https://gitlab.cern.ch/atlas/athena/-/merge_requests/41941 reduce verbosity of Epos_i