public static RuleDescriptionSectionDtoBuilder builder() {
    return new RuleDescriptionSectionDtoBuilder();
  }
@Test
  void setDefault_whenKeyAlreadySet_shouldThrow() {
    RuleDescriptionSectionDto.RuleDescriptionSectionDtoBuilder builderWithKey = RuleDescriptionSectionDto.builder()
      .key("tagada");
    assertThatExceptionOfType(IllegalArgumentException.class)
      .isThrownBy(builderWithKey::setDefault)
      .withMessage("Only one of setDefault and key methods can be called");
  }