Update Instrument.cs to match API changes in 1.22.0-rc.4#9

GeneralMangerTim wants to merge 2 commits into

Quacksol:mainQuacksol/vsinstruments_base:mainfrom

GeneralMangerTim:GeneralMangerTim-patch-1-GetPos()-API-updateGeneralMangerTim/vsinstruments_base_1.22.0-rc.4:GeneralMangerTim-patch-1-GetPos()-API-updateCopy head branch name to clipboard