v2.3.1

What's Changed

• Drop support for Python 3.7/3.8
• Add support for Python 3.13
• Remove deprecated tests_require from setup.py
• Update copyright years
• Refactor type annotations
• Bump sigstore/gh-action-sigstore-python from 2.1.1 to 3.0.0 in the actions-dependencies group by @dependabot in #50

Full Changelog: v2.3.0...v2.3.1