Investigate use of tsv-groupdata-parser

[RobH123]

https://github.com/unfoldingWord/tsv-groupdata-parser

This is the package that tC uses to read TSV files. So if this fails, tC fails.

If the CV checker used this, it could potentially ensure that tC can load the files.

The disadvantage is that the normal function gets passed file/folderpaths, whereas the CV package stores files in indexDB rather than in the local filesystem.