[hotfix] Fix MQTT test
[hotfix] Fix MQTT test

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