Bump pyo3 from 0.16.4 to 0.20.2

Bumps [pyo3](https://github.com/pyo3/pyo3) from 0.16.4 to 0.20.2.
- [Release notes](https://github.com/pyo3/pyo3/releases)
- [Changelog](https://github.com/PyO3/pyo3/blob/v0.20.2/CHANGELOG.md)
- [Commits](PyO3/pyo3@v0.16.4...v0.20.2)

---
updated-dependencies:
- dependency-name: pyo3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>