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-ushah2020/

Open the repository settings to inspect the description, then open README and compare both URLs with the target URL given in the issue. Update both references so they point to https://githubschool.github.io/github-games-ushah2020/; the repository description and README should no longer point to githubschool's copy.

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