Bump org.springframework:spring-framework-bom from 6.0.19 to 6.0.20

Bumps [org.springframework:spring-framework-bom](https://github.com/spring-projects/spring-framework) from 6.0.19 to 6.0.20.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](https://github.com/spring-projects/spring-framework/compare/v6.0.19...v6.0.20)

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

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

gradle/libs.versions.toml

@@ -13,7 +13,7 @@ org-jetbrains-kotlin = "1.8.22"
 org-jetbrains-kotlinx = "1.6.4"
 org-mockito = "4.8.1"
 org-opensaml = "4.1.1"
-org-springframework = "6.0.19"
+org-springframework = "6.0.20"
 
 [libraries]
 ch-qos-logback-logback-classic = "ch.qos.logback:logback-classic:1.4.14"