Update MacOS runner and revert #1443

[coruscating]

Reverts #1443 since dulwich made a new release with @wshanks's fix. Also updates the mac test runner to macos-13 since macOS-latest is now arm-based and no longer supports python3.8. We should eventually follow Qiskit/qiskit#12102 and add arm support.

[wshanks]

There has been no movement on the issue I linked to in #1421. I don't really understand how some things in GitHub are managed. You would think an employee could take a moment and review and approve the simple PR that would let Python 3.8 and 3.9 work on macos-latest. I think we might have to choose to skip 3.8 on macos or split and do 3.8 on macos-13 and 3.12 on macos-latest because 3.8 and 3.9 might never be enabled on macos-latest. (We could also install Python 3.8 outside of setup-python if we wanted).

[coruscating]

@wshanks Oh right, I forgot you already had that draft PR. It's unfortunate GitHub didn't address this before changing themacos-latest image without much notification. The split tests seem like a good solution that doesn't add testing overhead. I'll merge this for now just to get CI moving again.

[wshanks]

Maybe GitHub is monitoring this repo -- they fixed Python 3.8 on macos-latest right after I complained about it here!