Remove Python 3.7 and 3.8 from and add Python 3.12 to the build tests

[jeongyoonlee]

Proposed changes

Python 3.7 and 3.8 reached the End-Of-Life (EOL) in 6/2023 and 10/2024, respectively. This PR will drop both versions of Python from the build tests.

Adding Python 3.12 might require removing the Cython version restriction, which needs #803.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING doc
• I have signed the CLA
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

N/A