Bump org-opensaml5 from 5.1.2 to 5.1.5

Bumps `org-opensaml5` from 5.1.2 to 5.1.5.

Updates `org.opensaml:opensaml-saml-api` from 5.1.2 to 5.1.5

Updates `org.opensaml:opensaml-saml-impl` from 5.1.2 to 5.1.5

---
updated-dependencies:
- dependency-name: org.opensaml:opensaml-saml-api
  dependency-version: 5.1.5
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.opensaml:opensaml-saml-impl
  dependency-version: 5.1.5
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

gradle/libs.versions.toml

@@ -11,7 +11,7 @@ org-eclipse-jetty = "11.0.26"
 org-jetbrains-kotlin = "2.2.0"
 org-jetbrains-kotlinx = "1.10.2"
 org-mockito = "5.17.0"
-org-opensaml5 = "5.1.2"
+org-opensaml5 = "5.1.5"
 org-springframework = "7.0.0-M7"
 
 [libraries]