private static boolean onlyTestAndSetConditionFailed(Stream<Error> errors) {
        return errors.allMatch(e -> e.getCode() == DocumentProtocol.ERROR_TEST_AND_SET_CONDITION_FAILED);
    }
Returns true if every error in a stream is a test and set condition failed
vespaclient-core/src/main/java/com/yahoo/clientmetrics/MessageTypeMetricSet.java