Ballot fix: remove medicationReference typing from 4 medication profiles from R4 HL7AU medication to R4 Base medication

[udaychandrupatla]

medicationReference typing has been removed from these 4 profiles from R4 HL7AU medication to R4 Base medication

• AU Base Medication Administration
• AU Base Medication Dispense
• AU Base Medication Request
• AU Base Medication Statement

Addresses ballot comment FHIRIG-183