Merge branch 'sTGC_SDOPosition' into 'master'

Manually cherry-pick !31721 from 21.3 to master

See merge request atlas/athena!31810

MuonSpectrometer/MuonDigitization/sTGC_Digitization/src/sTgcDigitizationTool.cxx

@@ -591,7 +591,10 @@ StatusCode sTgcDigitizationTool::doDigitization() {
             std::vector<MuonSimData::Deposit> deposits;
             deposits.push_back(deposit);
             MuonSimData simData(deposits, hit.particleEncoding());
-            simData.setPosition(hit.globalPosition());
+            // The sTGC SDO should be placed at the center of the gap, same as the digits.
+            // We use the position from the hit on the wire surface which is by construction in the center of the gap
+            // G_HITONSURFACE_WIRE projects the whole hit to the center of the gap
+            simData.setPosition(G_HITONSURFACE_WIRE);
             simData.setTime(globalHitTime);
 
             // Associate the digit to the appropriate readout channel