docs: public BigMoney multipliedBy(BigDecimal valueToMultiplyBy) {
          MoneyUtils.checkNotNull(valueToMultiplyBy, "Multiplier must not be null");
          if (valueToMultiplyBy.compareTo(BigDecimal.ONE) == 0) {
              return this;
          }
          BigDecimal newAmount = amount.multiply(valueToMultiplyBy);
          return BigMoney.of(currency, newAmount);
      }