OpenSAML expects type `long` representing millis for response time validation skew

Fixes gh-7448

https://github.com/spring-projects/spring-security/issues/7448

saml2/saml2-service-provider/src/main/java/org/springframework/security/saml2/provider/service/authentication/OpenSamlAuthenticationProvider.java

@@ -253,7 +253,7 @@ public final class OpenSamlAuthenticationProvider implements AuthenticationProvi
 		validationParams.put(SAML2AssertionValidationParameters.SIGNATURE_REQUIRED, false);
 		validationParams.put(
 				SAML2AssertionValidationParameters.CLOCK_SKEW,
-				this.responseTimeValidationSkew
+				this.responseTimeValidationSkew.toMillis()
 		);
 		validationParams.put(
 				SAML2AssertionValidationParameters.COND_VALID_AUDIENCES,