Fix Delta R calculation
Fix Delta R calculation based on @vekirseb's findings: see https://indico.cern.ch/event/1439873/contributions/6059155/subcontributions/494452/attachments/2900475/5086366/xgboostNewAnaProd_July_2024.pdf
Relies on lhcb-datapkg/ParamFiles!106 (merged)
Edited by Andy Morris