Quiz answer incorrect: Part 9 -> 1 - Inheritance

[Luxxer1]

Hi! 👋

I found an error in the answer for the Inheritance quiz in Part 9 - 1 Inheritance.

I debugged the code and confirmed that the correct result should be 2, but the website currently shows 8.

Here is a small example demonstrating the issue:

Counter counter = new Counter();
Counter superCounter = new SuperCounter();
int number = 3;

number = superCounter.subtractFromNumber(number); // 3 - 1 = 2
number = superCounter.subtractFromNumber(number); // 2 - 1 = 1
number = counter.addToNumber(number);             // 1 + 1 = 2

System.out.println(number); // Correct output: 2

I tried to fix the issue via a pull request, but I realized that the quiz content comes from the backend database. To make it easier for the maintainers to locate the quiz, here is the quiz ID with the incorrect answer:

<quiz id="6b36458c-2d7a-55ac-9d28-4c0e1fcaf490"></quiz>

Thanks for looking into this!