Bump org.springframework.boot:spring-boot-gradle-plugin

Bumps [org.springframework.boot:spring-boot-gradle-plugin](https://github.com/spring-projects/spring-boot) from 3.4.3 to 4.0.2.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v3.4.3...v4.0.2)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-gradle-plugin
  dependency-version: 4.0.2
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

buildSrc/build.gradle.kts

@@ -14,7 +14,7 @@ repositories {
 dependencies {
     val kotlin = "2.1.10"
     val helm = "2.2.0"
-    implementation("org.springframework.boot:spring-boot-gradle-plugin:3.4.3")
+    implementation("org.springframework.boot:spring-boot-gradle-plugin:4.0.2")
     implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin")
     implementation("org.jetbrains.kotlin:kotlin-serialization:$kotlin")
     implementation("org.jetbrains.kotlin:kotlin-allopen:$kotlin")