Spring Security Saml2LogoutRequestMixin relayState property should be binding

Describe the bug It seems relayState property should be binding

To Reproduce

class Saml2LogoutRequestMixin {
..
  @JsonProperty("relayState") Saml2MessageBinding relayState,

Expected behavior

class Saml2LogoutRequestMixin {
..
  @JsonProperty("binding") Saml2MessageBinding binding,