Bump zx from 8.0.2 to 8.1.1

Bumps [zx](https://github.com/google/zx) from 8.0.2 to 8.1.1.
- [Release notes](https://github.com/google/zx/releases)
- [Commits](google/zx@8.0.2...8.1.1)

---
updated-dependencies:
- dependency-name: zx
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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