Bump org.mapstruct:mapstruct in /plugins/gradle/example-client

Bumps [org.mapstruct:mapstruct](https://github.com/mapstruct/mapstruct) from 1.5.5.Final to 1.6.0.
- [Release notes](https://github.com/mapstruct/mapstruct/releases)
- [Changelog](https://github.com/mapstruct/mapstruct/blob/main/NEXT_RELEASE_CHANGELOG.md)
- [Commits](mapstruct/mapstruct@1.5.5.Final...1.6.0)

---
updated-dependencies:
- dependency-name: org.mapstruct:mapstruct
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

plugins/gradle/example-client/build.gradle

@@ -27,8 +27,8 @@ dependencies {
     implementation "org.apache.httpcomponents:httpclient:4.5.14"
     implementation "javax.validation:validation-api:2.0.1.Final"
 
-    implementation "org.mapstruct:mapstruct:1.5.5.Final"
-    annotationProcessor "org.mapstruct:mapstruct-processor:1.5.5.Final"
+    implementation "org.mapstruct:mapstruct:1.6.0"
+    annotationProcessor "org.mapstruct:mapstruct-processor:1.6.0"
 
     compileOnly "org.projectlombok:lombok:1.18.30"
     annotationProcessor "org.projectlombok:lombok:1.18.30"