URL in description and README broken

The URL in the repository description and README are pointing to githubschool's copy of the game instead of yours.

Please fix both so they point to your copy of the game at https://githubschool.github.io/github-games-debmandel/

更新儲存庫描述和 README 中的 URL，使其指向指定的遊戲副本。檢查這兩個位置，然後驗證每個連結都能解析到 https://githubschool.github.io/github-games-debmandel/。

由索引模型根據 Issue 內容生成。