build(deps): bump io.micronaut:micronaut-http from 4.1.11 to 4.3.9

Bumps [io.micronaut:micronaut-http](https://github.com/micronaut-projects/micronaut-core) from 4.1.11 to 4.3.9.
- [Release notes](https://github.com/micronaut-projects/micronaut-core/releases)
- [Changelog](https://github.com/micronaut-projects/micronaut-core/blob/4.3.x/RELEASE.adoc)
- [Commits](micronaut-projects/micronaut-core@v4.1.11...v4.3.9)

---
updated-dependencies:
- dependency-name: io.micronaut:micronaut-http
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

server/jikkou-api-client/pom.xml

@@ -23,7 +23,7 @@
     <properties>
         <license.header.file>${project.parent.basedir}/header</license.header.file>
         <okhttp.version>4.12.0</okhttp.version>
-        <micronaut-http.version>4.1.11</micronaut-http.version>
+        <micronaut-http.version>4.3.9</micronaut-http.version>
     </properties>
 
     <dependencyManagement>