py: drop obsolete setuptools_scm_git_archive dependency

[Devansh-567]

Summary

This PR removes setuptools_scm_git_archive from py/pyproject.toml's build-system.requires.

setuptools_scm_git_archive has been archived and is no longer actively maintained. Modern versions of setuptools_scm no longer require it as a separate build dependency for standard versioning workflows, making this dependency unnecessary.

Removing the obsolete dependency simplifies the project's build requirements and reduces maintenance overhead.

Changes

• Removed setuptools_scm_git_archive from build-system.requires in py/pyproject.toml.

Testing

• Verified that this change only removes an unused build dependency.
• No functional source code changes were made.

[matthewtlam]

When asking AI whether it is safe to remove the git_archive, it recommends "setuptools_scm[toml]>=7.0.0"

Longer version of comment:

It was originally created as a plugin to allow setuptools_scm to read version numbers from .git_archival.txt files when building from a downloaded GitHub .tar.gz or .zip source archive (where the .git directory is missing).  However, starting with setuptools_scm version 7.0.0, this functionality was built directly into the core package.  If you remove it, you should ideally pin your setuptools_scm requirement to version 7.0.0 or higher to ensure the native git archive fallback still works.