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-benmachart

Update the URL in the repository description and README, replacing githubschool's copy with https://githubschool.github.io/github-games-benmachart. Review both locations first, then verify that each points to the repository's own game page.

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