Bump async-executor from 1.6.0 to 1.8.0

Bumps [async-executor](https://github.com/smol-rs/async-executor) from 1.6.0 to 1.8.0.
- [Release notes](https://github.com/smol-rs/async-executor/releases)
- [Changelog](https://github.com/smol-rs/async-executor/blob/master/CHANGELOG.md)
- [Commits](smol-rs/async-executor@v1.6.0...v1.8.0)

---
updated-dependencies:
- dependency-name: async-executor
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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