Update org.springframework:spring-framework-bom to 6.1.0-RC1

Closes gh-14023

gradle/libs.versions.toml

@@ -13,7 +13,7 @@ org-jetbrains-kotlin = "1.9.10"
 org-jetbrains-kotlinx = "1.7.3"
 org-mockito = "5.5.0"
 org-opensaml = "4.3.0"
-org-springframework = "6.1.0-M5"
+org-springframework = "6.1.0-RC1"
 
 [libraries]
 ch-qos-logback-logback-classic = "ch.qos.logback:logback-classic:1.4.11"