Pyproject.toml Template - Initial Release

What's Changed

• upstream merge template repository by @github-actions in #5
• Update tox.ini by @laserprec in #23
• Create pyproject.toml by @dciborow in #20

New Contributors

• @laserprec made their first contribution in #23

Full Changelog: https://github.com/microsoft/python-package-template/commits/1.0.0