Applying same split-level settings to DAOD_TRUTH formats as for PHYS, PHYSLITE

Applying same split-level settings to DAOD_TRUTH formats as for PHYS, PHYSLITE

It's been noted some of the branches of the TRUTHx formats aren't fully split into AuxDyn branches as they are in PHYS and PHYSLITE, meaning the TRUTH formats can't be trivially read with uproot. This MR makes the following changes:
- adds the TRUTH formats to the list of non-default streams for which full splitting should be applied
- switches to if statements from elif, to allow the settings to become progressively more specialised
- deletes a format type that doesn't exist and is unlikely to ever exist (D2AOD_PHYSLITE)

Database/AthenaPOOL/AthenaPoolCnvSvc/python/PoolWriteConfig.py

@@ -73,6 +73,7 @@ def PoolWriteCfg(flags):
         "DAOD_PHYSVAL"   : [5, 5,  100, 0, 1],
         "DAOD_PHYS"      : [5, 5,  500, 0, 1],
         "DAOD_PHYSLITE"  : [5, 5,  500, 1, 1],
+        "DAOD_TRUTH3"    : [5, 5,  500, 1, 1],
         "D2AOD_PHYSLITE" : [5, 5,  500, 1, 1],
     }