add prerequisities for high scores exercise

[AnishDe12020]

I have added the prerequisites for the high scores exercise.

references #984

[github-actions]

Dear AnishDe12020

Thank you for contributing to the JavaScript track on Exercism! 💙
You will see some automated feedback below 🤖. It would be great if you can make sure your PR covers those points. This will save your reviewer some time and your change can be merged quicker.

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