Update webpki requirement from 0.21 to 0.22 (#267)

* Update webpki requirement from 0.21 to 0.22

Updates the requirements on [webpki](https://github.com/briansmith/webpki) to permit the latest version.
- [Release notes](https://github.com/briansmith/webpki/releases)
- [Commits](https://github.com/briansmith/webpki/commits

)

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

* update webpki

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Niklas Adolfsson <[email protected]>