[stubsabot] Bump waitress to 3.0.*

[github-actions[bot]]

Release: https://pypi.org/pypi/waitress/3.0.0 Homepage: https://github.com/Pylons/waitress Repository: https://github.com/Pylons/waitress Changelog: https://docs.pylonsproject.org/projects/waitress/en/latest/index.html#change-history Diff: https://github.com/Pylons/waitress/compare/v2.1.2...v3.0.0

Stubsabot analysis of the diff between the two releases:

• Total lines of Python code added: 104.
• Total lines of Python code deleted: 125.

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