Update plugin org.springframework.boot to v3.4.0 (#140)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

build.gradle

@@ -1,6 +1,6 @@
 plugins {
   id 'java'
-  id 'org.springframework.boot' version '3.3.6'
+  id 'org.springframework.boot' version '3.4.0'
   id 'io.spring.dependency-management' version '1.1.6'
 }