Bump libsodium-rs from 0.2.3 to 0.2.4

Bumps [libsodium-rs](https://github.com/jedisct1/libsodium-rs) from 0.2.3 to 0.2.4.
- [Release notes](https://github.com/jedisct1/libsodium-rs/releases)
- [Commits](https://github.com/jedisct1/libsodium-rs/commits)

---
updated-dependencies:
- dependency-name: libsodium-rs
  dependency-version: 0.2.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]