chore(deps): update plugin org.sonarqube to v6 (!40)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| org.sonarqube | `5.1.0.4882` -> `6.0.1.5171` | [![age](https://developer.mend.io/api/mc/badges/age/maven/org.sonarqube:org.sonarqube.gradle.plugin/6.0.1.5171?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.sonarqube:org.sonarqube.gradle.plugin/6.0.1.5171?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.sonarqube:org.sonarqube.gradle.plugin/5.1.0.4882/6.0.1.5171?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.sonarqube:org.sonarqube.gradle.plugin/5.1.0.4882/6.0.1.5171?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Configuration

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Reviewed-on: #40
Co-authored-by: Renovate <renovate@kjan.de>
Co-committed-by: Renovate <renovate@kjan.de>

build.gradle.kts

@@ -3,7 +3,7 @@ plugins {
     id("org.springframework.boot") version "3.3.4"
     id("io.spring.dependency-management") version "1.1.6"
     id("checkstyle")
-    id("org.sonarqube") version "5.1.0.4882"
+    id("org.sonarqube") version "6.0.1.5171"
     id("jacoco")
 }