unkey 0.6.0

An asynchronous Rust SDK for the Unkey API.
Documentation
## Summary

<!-- A small summary of the requested changes -->

## Checklist

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- [x] Correct
- [X] Correct
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- [ ] I have run `cargo test` and all tests pass.
- [ ] I have run `cargo fmt` and the code is formatted.
- [ ] I have run `cargo clippy` in pedantic mode and refactored.
- [ ] I have included documentation for any new structs or methods.
- [ ] I have updated tests for any code I addded/changed/deleted.
- [ ] I have updated the CHANGELOG to include my changes.

## Related Issues

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