Once gen2 has been removed, the base class and configs for the new ConvertReferenceCatalog should be moved out of ingestIndexReferenceTask.py and into convertReferenceCatalog.py. We could potentially remove the base class entirely at that point, and just have ConvertReferenceCatalog by itself; the base class was just to let gen2/3 share most of the working code. See the note at the top of ingestIndexReferenceTask.py

Those cannot be moved until post-gen2, because the gen2 refcat config files have an explicit check that DatasetConfig live in ingestIndexReferenceTask.