build(deps): update itertools requirement from 0.11.0 to 0.12.0

Updates the requirements on [itertools](https://github.com/rust-itertools/itertools) to permit the latest version.
- [Changelog](https://github.com/rust-itertools/itertools/blob/master/CHANGELOG.md)
- [Commits](rust-itertools/itertools@v0.11.0...v0.12.0)

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

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

codegen/Cargo.toml

@@ -22,6 +22,6 @@ heck = "0.4.1"
 proc-macro2 = "1.0.50"
 quote = "1.0.23"
 rand = "0.8.5"
-itertools = "0.11.0"
+itertools = "0.12.0"
 syn = {version = "2.0.4", features = ["full", "visit", "visit-mut"]}
 portrait-framework = {version = "0.3.0", path = "../framework"}