Bump webpki from 0.22.1 to 0.22.4 in /services/commtest

Bumps [webpki](https://github.com/briansmith/webpki) from 0.22.1 to 0.22.4.
- [Commits](https://github.com/briansmith/webpki/commits)

---
updated-dependencies:
- dependency-name: webpki
  dependency-type: indirect
...

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Author: dependabot[bot]