Masking of file download url from S3

[ilkayholt]

Descriptive summary

This feature is to be added to the Hyku roadmap. Please see the labels for who works on it and check the board for the status.

Rationale

The user story that describes "why" this issue should be addressed: As a repository manager, I would like to secure URLs for downloading files in terms of revealing them to the end user and redirecting them in case of a storage relocation.

[ilkayholt]

Code file provided by the Ubiquity Press can be found at https://github.com/ubiquitypress/hyku_addons/blob/main/app/services/hyku_addons/file_signed_url_service.rb