Add MuonGeoModelCfg to the tracking geometry svc

This adds the muon geometry model service into component accumulator created by the tracking geometry service if muons are requested. If this is isn't present then attempting to retrieve this service crashes.

This is demonstrated with this MWE. I've attached an example run log showing the crash.

Given that component accumulators are meant to contain everything (apart from some core services like the StoreGate) that is needed for a component to function, I think this is the appropriate place to add the service.

Tests:

• Adding the MuonGeoModelSvc into the MWE allows it to run without crashing
• With the fix in this MR the MWE can run without crashing
• Explicitly setting ConfigFlags.Detector.MuonGeometry = False in the MWE also prevents the crash (as the problematic tool is never built)