Resolve "Some paths of a device cant be requested more than once"

nucleus/southbound.go

@@ -114,7 +114,10 @@ func unmarshal(schema *ytypes.Schema, bytes []byte, fields []string, goStruct yg
 		return err
 	}
 	ygot.PruneEmptyBranches(validatedDeepCopy)
-	return ygot.MergeStructInto(goStruct, validatedDeepCopy)
+
+	opts := []ygot.MergeOpt{&ygot.MergeOverwriteExistingFields{}}
+
+	return ygot.MergeStructInto(goStruct, validatedDeepCopy, opts...)
 }
 
 // getField traverses the GoStruct and returns the field that represents the