Apply Detector component cannot handle trailing empty line

[pschaldenbrand]

When the input transaction file has a trailing empty line, I get an NPE at:

DetectorTester/program/CTAT-detector-plugins/Test_Rig/Test_Rig_WorkflowComponent.js:171
tutorSelection = stepName.split(" ")[0];

This component should be able to handle these trailing empty lines as many files have them. At the very least, we should output an error that has a proactive message.