fixed test error in deserializing device identifiers by reworking logic of placeholder device id

java/com.sap.sailing.server.gateway.serialization/src/com/sap/sailing/server/gateway/deserialization/impl/DeviceIdentifierJsonDeserializer.java

@@ -40,7 +40,11 @@ public class DeviceIdentifierJsonDeserializer implements JsonDeserializer<Device
         try {
             return deviceServiceFinder.findService(deviceType).deserialize(deviceIdObject, deviceType, deviceStringRep);
         } catch (TransformationException e) {
-            throw new JsonDeserializationException(e);
+            try {
+            return new PlaceHolderDeviceIdentifierJsonHandler().deserialize(deviceIdObject, deviceType, deviceStringRep);
+            } catch (TransformationException e2) {
+                throw new JsonDeserializationException(e2);
+            }
         }
     }