build(deps): update itertools requirement from 0.10.5 to 0.12.1 (#390)

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](https://github.com/rust-itertools/itertools/compare/v0.10.5...v0.12.1)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pallas-network/Cargo.toml

@@ -13,7 +13,7 @@ authors = ["Santiago Carmuega <santiago@carmuega.me>", "Pi Lanningham <pi.lannin
 [dependencies]
 byteorder = "1.4.3"
 hex = "0.4.3"
-itertools = "0.10.5"
+itertools = "0.12.1"
 pallas-codec = { version = "=0.22.0", path = "../pallas-codec" }
 pallas-crypto = { version = "=0.22.0", path = "../pallas-crypto" }
 rand = "0.8.5"