Feature/fixes pr

[Titiftw]

:tophat: What? Why?

• [x] When playing, there was a bug when a player would reconnect more than once which could potentially happen. I fixed it in my feature branch (now the player can refresh any time the game, as long as it is not answering a question).
• [x] When playing, the total score showed on the player screen was wrong if the player reconnected.
• [x] When playing, a player could give X answers if it would click X times on the "Validate" button. I adjusted the disabled button logic in the frontend and also return an "already_replied" on the WebSocket.
• [x] When playing on a CHECK question, the player could select multiple answers. I made sure all the selected answers were removed when clicking on anoth

Testing

Join a quiz and refresh twice the page. Previously, the second refresh would end up on the Quiz code input.

:hearts: Thank you!

[mawoka-myblock]

Please don't create a PR depending on another one. It'll make it even more complex. I'll ignore this PR for now until we figure #401 out if that's fine for you