Update jiter requirement from 0.4 to 0.6

Updates the requirements on [jiter](https://github.com/pydantic/jiter) to permit the latest version.
- [Release notes](https://github.com/pydantic/jiter/releases)
- [Commits](pydantic/jiter@v0.4.0...v0.6.0)

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

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

arrow-open-variant/Cargo.toml

@@ -17,7 +17,7 @@ arrow-schema.workspace = true
 open-variant = { path = "../open-variant" }
 
 # For JSON parsing
-jiter = { version = "0.4", optional = true }
+jiter = { version = "0.6", optional = true }
 
 [features]
 default = ["json"]