Bump zx from 4.2.0 to 6.2.3

Bumps [zx](https://github.com/google/zx) from 4.2.0 to 6.2.3.
- [Release notes](https://github.com/google/zx/releases)
- [Commits](google/zx@4.2.0...6.2.3)

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

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