chore(deps): bump keccak from 0.1.5 to 0.1.6 (#2223)

Bumps [keccak](https://github.com/RustCrypto/sponges) from 0.1.5 to 0.1.6.
- [Commits](RustCrypto/sponges@keccak-v0.1.5...keccak-v0.1.6)

---
updated-dependencies:
- dependency-name: keccak
  dependency-version: 0.1.6
  dependency-type: indirect
...

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Co-authored-by: Hugo <235113615+hugo-stacks@users.noreply.github.com>

Author: dependabot[bot]