Bump the dev-dependencies group with 1 update (#57)

Updates the requirements on [iref](https://github.com/timothee-haudebourg/iref) to permit the latest version.
- [Changelog](https://github.com/timothee-haudebourg/iref/blob/main/CHANGELOG.md)
- [Commits](timothee-haudebourg/iref@2.1.0...2.2.3)

---
updated-dependencies:
- dependency-name: iref
  dependency-type: direct:production
  dependency-group: dev-dependencies
...

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

Cargo.toml

@@ -48,7 +48,7 @@ http = "0.2.9"
 http-body = "0.4.5"
 hyper = "0.14.27"
 image = "0.24.3"
-iref = "^2.0.3"
+iref = "^3.1.2"
 lazy_static = "1.4.0"
 log = "^0.4"
 paho-mqtt = "0.12"