Update plugin org.springframework.boot to v3.5.9

Author: renovate[bot]

build.gradle

@@ -13,7 +13,7 @@ plugins {
   id 'pmd'
   id 'jacoco'
   id 'io.spring.dependency-management' version '1.1.7'
-  id 'org.springframework.boot' version '3.3.5'
+  id 'org.springframework.boot' version '3.5.9'
   id 'org.owasp.dependencycheck' version '12.1.6'
   id 'com.github.ben-manes.versions' version '0.53.0'
   id 'org.sonarqube' version '6.3.1.5724'