create invoke task for making tests for new harvesters

[erinspace]

[kms6bn]

@erinspace should we consider this closed?

[erinspace]

@kms6bn I think this issue was originally referencing the automatic creation of a test for a new harvester, not running just one (which is AWESOME and totally needed). But I think that this issue still stands, we'd like to be able to auto create a new test w/yml file for a new harvester