xAODMuonTrkPrepRawData
This is a follow up to !67562 (closed), but relocating the PRD to xAOD convertor to an existing Muon package instead of an ACTS one. There was an existing MDT convertor which I deleted, since it is now replaced by the generic algorithm.
This also adds a new test, which currently doesn't do much except check that the convertor runs, but which will be expanded in the future.