Update rand requirement from 0.8.5 to 0.9.0

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@0.8.5...0.9.0)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Cargo.toml

@@ -10,7 +10,7 @@ debug = true
 [dependencies]
 fastly = "0.10.1"
 hmac-sha256 = "1.1.7"
-rand = "0.8.5"
+rand = "0.9.0"
 serde = { version = "1.0.203", features = ["derive"] }
 serde_json = "1.0.120"
 base64 = "0.22.1"