routing: update test to assert correctness of per-hop payloads
routing: update test to assert correctness of per-hop payloads

ddustin/lnd,ddustin/lnd,LightningNetwork/lnd,aakselrod/lnd,AndrewSamokhvalov/lnd,aakselrod/lnd,LightningNetwork/lnd,AndrewSamokhvalov/lnd