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

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] <[email protected]>

Author: dependabot[bot]

plugins/gradle/example-server/build.gradle

@@ -26,8 +26,8 @@ dependencies {
 
     implementation 'org.projectlombok:lombok-mapstruct-binding:0.2.0'
 
-    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"
 }
 
 compileJava.dependsOn "graphqlCodegen"