Fix `JobsController#raw` endpoint can not read traces in database

What does this MR do?

The brief summary of the current implementation

• When traces has been stored in FileStorage, JobsController can read the trace at raw endpoint
• When traces has been stored in ObjectStorage, JobsController can read the trace at raw endpoint
• When traces has been stored in Database, JobsController can not read the trace at raw endpoint
• When traces has been stored in FileStorage, JobsController can read the trace at trace endpoint
• When traces has been stored in ObjectStorage, JobsController can read the trace at trace endpoint
• When traces has been stored in Database, JobsController can read the trace at trace endpoint

This MR fixes the following bugs

• When traces has been stored in Database, JobsController can not read the trace at raw endpoint

Ideally, we should have this before fixing this

• https://gitlab.com/gitlab-org/gitlab-ce/issues/44820 (Introduce use_stream and send_stream methods)

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Tests added for this feature/bug
• Review
  • Has been reviewed by Backend
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #44665 (closed)