    @Test
    public void convertWhenSimpleWithoutSuffixShouldReturnDuration() {

        assertThat(convert("10")).isEqualTo(Duration.ofMillis(10));
        assertThat(convert("+10")).isEqualTo(Duration.ofMillis(10));
        assertThat(convert("-10")).isEqualTo(Duration.ofMillis(-10));
    }