Follow-up: Github markdown image import for private repos before May 9 2023

Currently the only thing missing from importing Github markdown image attachments is supporting private repositories that have images uploaded before May 9th 2023.

Github changed how their attachments are handled: https://github.blog/changelog/2023-05-09-more-secure-private-attachments/, see comment.

This is difficult to do now because of 2 reasons

1. We have no example of this scenario. I don't think anyone on the team has a private repo with images attached before may 9th. Therefore we can't test or have visibility into this. Will have to wait for a customer's example.
   1. https://gitlab.slack.com/archives/C04UYQV7716/p1693522970293969
2. We can however estimate what it would looks like. I'd image it'll look something like https://private-user-images.githubusercontent.com/142635249/265130289-56ac7a5a-cc77-4c44-8a1b-5a4affbd237b.jpg
   1. Getting this image is made harder due to: https://github.com/orgs/community/discussions/54551#discussioncomment-5903362
      1. With a 5-min expiring JWT for the image upon page rendering, this makes it hard to get any private images via what we're currently doing now (scraping the issue text via api and not interacting)
   2. There is no api alternative for this currently

Proposed way forward

Document this problem in the docs, link to this issue and close it until we know about a customer experiencing this problem.