metadata export API exports metadata from harvested datasets, caches locally

[donsizemore]

I noticed this on v5.9 but reproduced the behavior on v5.13 this morning.

When an anonymous user calls the /api/datasets/export API endpoint using the DOI of a harvested dataset, Dataverse writes out the export_format.cached file in a directory structure appropriate to the originating instance, then returns the file.

I asked in Slack because Dataverse reports the parent collection (root dataverse) as the publisher.

Proposed corrections included preventing Dataverse from exporting harvested metadata, or redirecting (via 301 or text response) to the primary Dataverse instance, as would happen in the GUI.