Used regular array and added it as a field inside UBullCowCartridge.h

As we’re not planning to update our list, I used a regular array and placed it inside header file as it’s not too big anyway. Mine is 8 words long:

class BULLCOWGAME_API UBullCowCartridge : public UCartridge
{
    // ...
private:
    const FString HiddenWords[8] = {
        TEXT("car"), TEXT("row"),
        TEXT("duck"), TEXT("game"),
        TEXT("chair"), TEXT("table"),
        TEXT("flower"), TEXT("change")
    };
    // ...
}

Noticed that I needed to provide array length right away. Without it the code wouldn’t compile