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-jltillis

Open the README and repository description, then compare their current game URLs with the target URL given in the issue. Update both references so they point to the specified copy, and verify that the README and description no longer link to the incorrect game location.

索引モデルが issue の本文から書いたものです。