Bump rand from 0.7.3 to 0.9.3 in /tools/html-bench

Bumps [rand](https://github.com/rust-random/rand) from 0.7.3 to 0.9.3.
- [Release notes](https://github.com/rust-random/rand/releases)
- [Changelog](https://github.com/rust-random/rand/blob/0.9.3/CHANGELOG.md)
- [Commits](rust-random/rand@0.7.3...0.9.3)

---
updated-dependencies:
- dependency-name: rand
  dependency-version: 0.9.3
  dependency-type: direct:production
...

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

Author: dependabot[bot]

tools/html-bench/Cargo.lock

@@ -8,5 +8,5 @@ edition = "2018"
 
 [dependencies]
 structopt = "0.3.20"
-rand = { version = "0.7.3", features = ["small_rng"] }
+rand = { version = "0.9.3", features = ["small_rng"] }
 anyhow = "1.0.33"