Bump ed25519-dalek from 2.1.0 to 2.1.1

Bumps [ed25519-dalek](https://github.com/dalek-cryptography/curve25519-dalek) from 2.1.0 to 2.1.1.
- [Release notes](https://github.com/dalek-cryptography/curve25519-dalek/releases)
- [Changelog](https://github.com/dalek-cryptography/curve25519-dalek/blob/2.1.1/CHANGELOG.md)
- [Commits](dalek-cryptography/curve25519-dalek@2.1.0...2.1.1)

---
updated-dependencies:
- dependency-name: ed25519-dalek
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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