@Test
 public void givenAnItemWithANegativeSellin_thenTheSellinDayIsPassed() {
   InnItem innItem = new InnItem("Lambda", -1, 0);
   assertThat(innItem.isSellInDayPassed()).isTrue();
 }
 @Test
 public void givenAnItemWithAZeroSellin_thenTheSellinDayIsNotPassed() {
   InnItem innItem = new InnItem("Lambda", 0, 0);
   assertThat(innItem.isSellInDayPassed()).isFalse();
 }