@Test
    void verifyJsonWithToken() throws Throwable {
        val credentials = new SpnegoCredential(new byte[16]);
        credentials.setNextToken(new byte[16]);
        assertFalse(MAPPER.writeValueAsString(credentials).contains("initToken"));
        assertFalse(MAPPER.writeValueAsString(credentials).contains("nextToken"));
    }
Make sure that when the Principal becomes populated / changes we return a new hash
support/cas-server-support-spnego/src/test/java/org/apereo/cas/support/spnego/authentication/principal/SpnegoCredentialsTests.java