Use Specific Muon Roi in the ID Trigger monitoring

The Muon trigger creates a new RoiDescriptor, HLT_Roi_L2SAMuon for use by
the ID Trigger tracking. ( see atlas/athena!31747 )

This change allows the ID Trigger moniotirng to use the new RoiDescriptor.

Before the change in !31747 the ID Trigger muon moniotring does not work,
so this change is fine to go in before !31747