Update wheel to 0.33.6

[pyup-bot]

This PR updates wheel from 0.33.4 to 0.33.6.

Changelog

0.33.6

- Fixed regression from 0.33.5 that broke building binary wheels against the
limited ABI
- Fixed egg2wheel compatibility with the future release of Python 3.10
(PR by Anthony Sottile)

0.33.5

- Don't add the ``m`` ABI flag to wheel names on Python 3.8 (PR by rdb)
- Updated ``MANIFEST.in`` to include many previously omitted files in the sdist

Links

• PyPI: https://pypi.org/project/wheel
• Changelog: https://pyup.io/changelogs/wheel/
• Repo: https://github.com/pypa/wheel