Update itertools requirement from =0.10 to =0.11 (#180)

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@v0.10.0...v0.11.0)

---
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>

make-tzdb/Cargo.toml

@@ -12,7 +12,7 @@ publish = false
 anyhow = "=1"
 convert_case = "=0.6"
 indexmap = "=1"
-itertools = "=0.10"
+itertools = "=0.11"
 ron = "=0.8"
 serde = { version = "=1", features = ["derive"] }
 subprocess = "=0.2"