Bump org.springframework.boot in /samples/zip-split-rabbit-binder

Bumps [org.springframework.boot](https://github.com/spring-projects/spring-boot) from 3.4.2 to 3.4.3.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/compare/v3.4.2...v3.4.3)

---
updated-dependencies:
- dependency-name: org.springframework.boot
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

samples/zip-split-rabbit-binder/build.gradle

@@ -1,6 +1,6 @@
 plugins {
 	id 'java'
-	id 'org.springframework.boot' version '3.4.2'
+	id 'org.springframework.boot' version '3.4.3'
 	id 'io.spring.dependency-management' version '1.1.7'
 }