@Test
public void shouldOnlyUpdateWhenPropertyWasChanged() {

    observer.onDurationValue("daemonPollingInterval", null, duration -> this.daemonPollingInterval = duration);
    assertThat(daemonPollingInterval).isEqualTo(null);
    daemonPollingInterval = Duration.ofMinutes(5);
    writeConfigLines(
            "example.one=dummy2",
            "example.two=foobar2"
    );
    assertThat(daemonPollingInterval).isEqualTo(Duration.ofMinutes(5));
    writeConfigLine("daemonPollingInterval=PT1M");
    assertThat(daemonPollingInterval).isEqualTo(Duration.ofMinutes(1));
}