Final report enhancement

[vilarodr]

The final report from the upload should take in account more info from the repository side like for the API call "Replacing multiple existing files in the Dataset" that returns a JSON object as a response that includes a “data” that indicates how many of the file replacements (uploads in our case) succeeded and provides per-file error messages for those that don’t, e.g.

See https://guides.dataverse.org/en/latest/developers/s3-direct-upload-api.html#replacing-multiple-existing-files-in-the-dataset

The variable addMultipleFilesResponse on code line 127 at upload-controller could be used for this purpose.