Service Desk: Ticket attachment links sent in email notifications are broken. (4272747)

Steps to reproduce

1. Enable "Secure Service Desk Attachments" under Security Settings.
2. Create a Service Desk ticket with an attachment.
3. Copy the URL for the attachment.
4. Open a new tab in the browser while still logged in. (This is essentially the same as clicking on a link from an email.)

Expected results

The attachment should download inside your browser. If you were logged out of the system you should be redirected to the User Portal to login and then the attachment would download.

Actual Results

You get presented with a "Oops! Permission Denied" page.