remove deleted step from orderedSteps; better handle undefined steps in steplist (#1481)
remove deleted step from orderedSteps; better handle undefined steps in steplist (#1481)


Opentrons/labware,OpenTrons/opentrons-api,OpenTrons/opentrons_sdk,OpenTrons/opentrons-api,OpenTrons/opentrons-api,OpenTrons/opentrons-api,OpenTrons/opentrons-api