NPE in CoAP adapter on PUT request without device id in URI

[calohmn]

Found this exception in CoAP adapter logs:

java.lang.NullPointerException
	at java.base/java.util.Objects.requireNonNull(Unknown Source)
	at org.eclipse.hono.auth.Device.getPrincipal(Device.java:46)
	at org.eclipse.hono.auth.Device.<init>(Device.java:40)
	at org.eclipse.hono.adapter.coap.AbstractHonoResource.lambda$getPutRequestDeviceAndAuth$2(AbstractHonoResource.java:145)
	at java.base/java.util.Optional.ifPresentOrElse(Unknown Source)
	at org.eclipse.hono.adapter.coap.AbstractHonoResource.getPutRequestDeviceAndAuth(AbstractHonoResource.java:139)
	at org.eclipse.hono.adapter.coap.AbstractHonoResource.createCoapContextForPut(AbstractHonoResource.java:195)
	at org.eclipse.hono.adapter.coap.TracingSupportingHonoResource.handleRequest(TracingSupportingHonoResource.java:182)
	at org.eclipse.californium.core.server.ServerMessageDeliverer$1.run(ServerMessageDeliverer.java:129)
	at org.eclipse.hono.adapter.coap.HonoRootResource$1.lambda$execute$0(HonoRootResource.java:49)
	at io.vertx.core.impl.AbstractContext.dispatch(AbstractContext.java:100)