Deprecate Python 3.8, making 3.9 the oldest target Python version

[idavis]

Python 3.8 is EOL this month (October 2024).

Update Python package to target abi39 in Rust and >=3.9 in the Python project.

We can add 3.13 support at the same time.

This will require migrating manylinux build to use a newer image. Mariner2 should work as it uses Python 3.9 and glibc 2.35. This needs to be done in the ADO pipelines.

[idavis]

Fixed

[idavis]

Reopened as we encountered issue with manylinux builds in production pipeline. Issue has been updated with relevant information.