Refactor game to React Hooks

[itaditya]

1. Convert Game.js to functional component.
2. Use common React hooks like useState, useRef, useEffect.
3. Make sure existing tests pass without any change in test files.

[pavelkeyzik]

I can do this

[itaditya]

@pavelkeyzik my bad on opening this issue so early. I appreciate the hard work you have done and also the extra work done to refactor the new code introduced by PRs getting merged daily.

The reason I didn't merge it till now was that I wanted beginners to also contribute to the project. Once we add hooks to the code the learning curve will increase and so many beginners might be discouraged to work on the project.

Here's what I'll do, once the momentum of this project goes down, I'll comment here and give you the green flag. Then you can update the code once and I'll make sure I don't merge any other code before yours. I'll ensure your PR gets merged before Hacktoberfest is over. Cheers!

[pavelkeyzik]

@itaditya Okay! Sounds great 👍