Kiosk: Have user-added games display high scores if the game has it

[srietkerk]

Right now, there are two things that limit the implementation of this feature:

1. We automatically assign all user-added games to have "HighScore": "None"
2. Kiosk assumes high scores to be single ascending in the high score list component

Having user-added games with high scores is something that is a delighter for users. Was requested/asked about here: https://forum.makecode.com/t/kiosk-game-high-score-leader-board/28978/1