Export Descriptor List as Excel
Add "Download" descriptor list button next to "Print version" to the UI. No need to check published state.
Backend
Add option to download the descriptor list in the Catalog Excel format. The same excel template must be used as for exporting Datasets, but only "metadata" and "descriptor" sheets are used. The other sheets should be removed.
The endpoint can generate Excel on the fly (no need to store to repository).
Client must be authenticated to access the endpoint.