Promoting William Woodruff as maintainer of the PUG

[webknjaz]

Issue Description

@woodruffw's a trusted member of PyPA already, involved in packaging standards, PyPI etc. He's volunteered to be helping more with triaging stuff in this repo (#1899 (comment)).

cc @pypa/packaging-user-guide-editors could someone add him to the team?

Code of Conduct

• I am aware that participants in this repository must follow the PSF Code of Conduct.

[ewdurbin]

Done.