fix(deps): update managed.reactor to v3.5.9 (#9739)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

gradle/libs.versions.toml

@@ -69,7 +69,7 @@ managed-netty-http3 = "0.0.16.Final"
 managed-netty-tcnative = "2.0.61.Final"
 managed-reactive-streams = "1.0.4"
 # This should be kept aligned with https://github.com/micronaut-projects/micronaut-reactor/blob/master/gradle.properties from the BOM
-managed-reactor = "3.5.8"
+managed-reactor = "3.5.9"
 managed-snakeyaml = "2.0"
 managed-java-parser-core = "3.25.4"
 managed-ksp = "1.8.21-1.0.11"