Update rand requirement from 0.9 to 0.10

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@rand_core-0.9.1...0.10.0)

---
updated-dependencies:
- dependency-name: rand
  dependency-version: 0.10.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

Cargo.toml

@@ -135,7 +135,7 @@ unit_test_utils = "0.1.3"
 #       instead, use:
 icasadi_test = "0.0.2"
 # Random number generators for unit tests:
-rand = "0.9"
+rand = "0.10"
 
 
 # --------------------------------------------------------------------------