Validate SAML Assertion - Test case with expired cert in trust store and valid saml assertion

[#1]

Hi Team, need pointers on this test case

How will Validate SAML Assertion policy will handle this scenario, when the certificate configured in the trust store is expired and SAML assertion is valid?

[#2]

Am facing some issues to get the expired cert and add it in trust store to test however I believe its an equivalent no trust store case and am expecting the below error-

{"fault":"{\"detail\":{\"errorcode\":\"steps.saml.ERROR_VALIDATING_SIGNATURE\"},\"faultstring\":\"ValidateSAMLAssertion[Validate-SAML-Assertion]: Error during signature validation\"}"}