Guest user can't see the project's code in private repository
Description
After attempting to manage roles for my private repositories, I noticed that Guests are not allowed to see the code. It seems rather odd to me and I even thought it was a bug. I noticed #2907 (closed) mentioning this issue and it was closed in favor of #12736 (closed). However, the Custom Roles won't be implemented in the near future.
Would it be possible to have some intermediary solution in order to allow people to see the code but not manage labels and issues?
Proposal
Either adding the Pull project code and Download project permissions to the Guest role.
Or create a role between Guest and Reporter