[TECH DEBT] Remove support for Python 3.9 from pre-commit and requirements, and make GitHub Actions use Python provided by relenv

[dmurphy18]

Description of the tech debt to be addressed, include links and screenshots

Current GitHub actions is leveraging the system python on the build OS, for example: Rocky Linux uses Python 3.9, but Salt no longer supports system python with relenv, hence removing support for Python 3.9, and leveraging the Python version provided by relenv, currently Python 3.10.

[dmurphy18]

Closing this PR due to the following:

Working on that use of Python 3.10 for the github actions rather than the system Python, but running into an issue on Rocky Linux 9, in trying to do that, which raised an issue which I thought I'd share and get your opinion on.

Rocky Linux 9 uses Python 3.9, if were to use Python 3.10, not too much impedance mismatch, but when we eventually start using Python 3.13, or 3.14 (it is alpha 5 and probably released by time for 3008), that impedance mismatch may be too great and have issues with the rpm or apt tools from the system. Currently usage of Ubuntu 22.04 is not a problem since the system python is 3.10.

The easiest workflow would be to allow for Python 3.9 in pre-commit and requirements, and update that as OS's age out, which for Rock Linux 9 could be sometime.

Given the resources we have, path of least resistance and preventative issues in the future.