Warn about BIDS ID matching if dataset has imaging data

[alyssadai]

At the moment, if a user annotates a non-BIDS ID column in their phenotypic TSV as the participant ID, but then wants to include BIDS data in their JSONLD at the CLI step, they will need to go back and 1) add a new column with BIDS IDs to their TSVs and 2) re-annotate the TSV. This is pretty annoying, so we should instead have a clear warning during annotation that if a dataset has BIDS data that needs to be harmonized (or maybe if the user knows they intend to BIDSify data?), they should first generate and add BIDS IDs to the TSV before proceeding w/ the annotation.

[github-actions]

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