@Test
public void notAddingLiveResponseAckLabelToExplicitlyEmptyRequiredAckLabels() {

    final DittoHeaders dittoHeaders = DittoHeaders.newBuilder()
            .channel("live")
            .acknowledgementRequests(Collections.emptyList())
            .randomCorrelationId()
            .responseRequired(true)
            .build();
    final MessageCommand<?, ?> command = SendThingMessage.of(THING_ID, MESSAGE, dittoHeaders);
    final MessageCommandAckRequestSetter underTest = MessageCommandAckRequestSetter.getInstance();
    final DittoHeaders expectedHeaders = dittoHeaders.toBuilder()
            .acknowledgementRequests(Collections.emptyList())
            .build();
    final MessageCommand<?, ?> expectedCommand = command.setDittoHeaders(expectedHeaders);
    final MessageCommand<?, ?> appliedCommand = underTest.apply(command);
    assertThat(appliedCommand.getDittoHeaders()).isEqualTo(expectedHeaders);
    assertThat(appliedCommand).isEqualTo(expectedCommand);
}