@Transactional
    public void deleteUsedMemberCoupons(final Long buyerId, final List<Long> usedCoupons) {
        memberCouponRepository.deleteByMemberIdAndCouponIdIn(buyerId, usedCoupons);
    }
@Test
    void 멤버가_사용한_쿠폰을_모두_제거한다() {
        // given
        Coupon coupon = couponRepository.save(쿠픈_생성_독자_사용_할인율_10_퍼센트());
        MemberCoupon memberCoupon = memberCouponRepository.save(멤버_쿠폰_생성());

        // when
        couponService.deleteUsedMemberCoupons(memberCoupon.getMemberId(), List.of(coupon.getId()));

        // then
        List<MemberCoupon> result = memberCouponRepository.findAllByMemberId(memberCoupon.getMemberId());
        assertThat(result).isEmpty();
    }