@Test
public void testHeaderDoesntStartWithNegotiate() throws Exception {

    List<Map<String, String>> config = List.of(Map.of(
        "keytab", fakeKDC.getKeytabPath(BROKER).toString(),
        "principal", BROKER
    ));
    try (SettingsOverride override = SettingsOverride.apply(Map.of(AppSettings.KEYTABS, config))) {
        SpnegoAuthenticator auth = new SpnegoAuthenticator();
        try {
            auth.authenticateUser("xxx");
            fail();
        } catch (StatusRuntimeException e) {
            assertEquals(Status.UNAUTHENTICATED.getCode(), e.getStatus().getCode());
            assertEquals("UNAUTHENTICATED: Use \"authorization: Negotiate <token>\" metadata to authenticate", e.getMessage());
        }
    }
}