Missing reference to DIgital Twin Id

[RiccardoMorandi99]

Missing reference to DIgital Twin Id, generate this error: ERROR i.wldt.core.engine.DigitalTwinWorker - WLDT WORKER onWorkerStart ERROR: Error ! Impossible to start a DigitalTwinWorker with a NULL Digital Twin Id !

wldt-core-java/src/main/java/it/wldt/core/model/DigitalTwinModel.java

Line 46 in 618652a

super();