build: Bump io-uring from 0.6.3 to 0.6.4 in /fuzz

Bumps [io-uring](https://github.com/tokio-rs/io-uring) from 0.6.3 to 0.6.4.
- [Commits](https://github.com/tokio-rs/io-uring/commits)

---
updated-dependencies:
- dependency-name: io-uring
  dependency-type: indirect
  update-type: version-update:semver-patch
...

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