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-mrmatt151/

更新儲存庫描述和 README，issue 指出其中包含錯誤的 URL。將兩個連結替換為 https://githubschool.github.io/github-games-mrmatt151/，並驗證 README 中的連結和儲存庫描述都指向該目標位址。

由索引模型根據 Issue 內容生成。