URL in description and README broken

The URL in the repository description and the one in the 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-cs-witch/

開啟 README 和 repository 描述，然後將兩個 URL 與 issue 中所述的目標 URL 進行比較。更新每個參照，使其指向 https://githubschool.github.io/github-games-cs-witch/，並驗證兩個連結都能正確解析。

由索引模型根據 Issue 內容生成。