Bump org.springframework.boot from 3.1.8 to 3.1.9

Bumps [org.springframework.boot](https://github.com/spring-projects/spring-boot) from 3.1.8 to 3.1.9.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/compare/v3.1.8...v3.1.9)

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

Signed-off-by: dependabot[bot] <support@github.com>

gradle/libs.versions.toml

@@ -1,5 +1,5 @@
 [versions]
-org-springframework-boot = "3.1.8"
+org-springframework-boot = "3.1.9"
 
 [libraries]
 org-springframework-spring-framework-bom = "org.springframework:spring-framework-bom:6.0.17"