Refactor spreadsheet conversion #243
Description
Mostly for someone with Matlab > 2018a because I can't currently run it or write the required tests that would be required before refactoring.
- file to refactor: https://github.com/bids-standard/bids-starter-kit/blob/main/matlabCode/general/bids_spreadsheet2participants.m
- ideally we would like to get a complexity in the 20s rather than its current state