Use "digitalIdentifier" as @id?

[apdavison]

For nodes that have no @id, but which do have a digitalIdentifier property that is a valid IRI, we could use the digitalIdentifer as @id when saving to file.

e.g., this would be the ORCID for a Person node.

This is probably not the desired behaviour for EBRAINS curation pipelines, but might be a good option in other scenarios.