[test-handler] Fix few things according to HandleUp tests
[test-handler] Fix few things according to HandleUp tests

TheThingsNetwork/ttn,mgranberry/ttn,TheThingsNetwork/ttn,mgranberry/ttn,jvanmalder/ttn,LoRaWanSoFa/ttn,LoRaWanSoFa/ttn,mgranberry/ttn,TheThingsNetwork/ttn,jvanmalder/ttn,jvanmalder/ttn