public static RestServerConfig forPublic(Integer rebalanceTimeoutMs, Map<?, ?> props) {
        return new PublicConfig(rebalanceTimeoutMs, props);
    }
@Test
    public void testAdminListenersNotAllowingBlankStrings() {
        Map<String, String> props = new HashMap<>();
        props.put(RestServerConfig.ADMIN_LISTENERS_CONFIG, "http://a.b:9999, ,https://a.b:9999");
        assertThrows(ConfigException.class, () -> RestServerConfig.forPublic(null, props));
    }