Bump iref from 3.2.2 to 4.0.0 in /rust/case2geojson

Bumps [iref](https://github.com/timothee-haudebourg/iref) from 3.2.2 to 4.0.0.
- [Changelog](https://github.com/timothee-haudebourg/iref/blob/main/CHANGELOG.md)
- [Commits](timothee-haudebourg/iref@v3.2.2...v4.0.0)

---
updated-dependencies:
- dependency-name: iref
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

rust/case2geojson/Cargo.lock

@@ -5,7 +5,7 @@ edition = "2021"
 
 [dependencies]
 geojson = "1.0.0"
-iref = "3.2.2"
+iref = "4.0.0"
 json-ld = { version = "0.21.4" }
 oxigraph = { version = "0.5.6", default-features = false}
 serde_json = "1.0.149"