chore(deps): bump spin from 0.12.1 to 0.12.2 in /src/tests/rust_guests

Bumps [spin](https://github.com/mvdnes/spin-rs) from 0.12.1 to 0.12.2.
- [Changelog](https://github.com/zesterer/spin-rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mvdnes/spin-rs/commits)

---
updated-dependencies:
- dependency-name: spin
  dependency-version: 0.12.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]