Update rand requirement from 0.8 to 0.9

Updates the requirements on [rand](https://github.com/rust-random/rand) to permit the latest version.
- [Release notes](https://github.com/rust-random/rand/releases)
- [Changelog](https://github.com/rust-random/rand/blob/master/CHANGELOG.md)
- [Commits](rust-random/rand@0.8.0...0.9.0)

---
updated-dependencies:
- dependency-name: rand
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Cargo.toml

@@ -41,7 +41,7 @@ lazy_static = "1.4"
 log = "0.4"
 num-traits = "0.2"
 quick-error = "2"
-rand = "0.8"
+rand = "0.9"
 rand_chacha = "0.3"
 sha2 = "0.10"