[JSDCLOUD-6084] 403 error when viewing attachments as a Customer

Attachments added to the Issue Description throw a '403 forbidden' error when viewed by Service Desk Customers.

Create an issue on a Service Desk project. (Make sure that it has a valid request type)
As a Service Desk agent, edit the issue description, adding and linking an attachment on it. [ˆattachment]
As a Customer, open the ticket on the portal.
Click on the attachment link.

The attachment is previewed/downloaded.

The following error is displayed to the customer:

Encountered a "403 - Forbidden" error while loading this page.

Link the attachment on a new comment.

was cloned as

JSDCLOUD-8176 403 error when viewing attachments as a Customer for Next-Gen projects