HGTD_G4_SD → HGTD_DetDescr Relation

File in HighGranularityTimingDetector/HGTD_G4/HGTD_G4_SD	Includes file in HighGranularityTimingDetector/HGTD_DetDescr
src / HGTDSensorGmxSD.h	HGTD_Identifier / HGTD_Identifier / HGTD_ID.h
src / HGTDSensorSD.h	HGTD_Identifier / HGTD_Identifier / HGTD_ID.h