Bump spring-boot.version from 3.5.5 to 3.5.6

Bumps `spring-boot.version` from 3.5.5 to 3.5.6.

Updates `org.springframework.boot:spring-boot-starter-parent` from 3.5.5 to 3.5.6
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/compare/v3.5.5...v3.5.6)

Updates `org.springframework.boot:spring-boot-maven-plugin` from 3.5.5 to 3.5.6
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/compare/v3.5.5...v3.5.6

)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-starter-parent
  dependency-version: 3.5.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.springframework.boot:spring-boot-maven-plugin
  dependency-version: 3.5.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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