Make a MD table in root for Challenges.

[AdarshRise]

Make a table in the main readme at root level

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@AdarshRise achieved the badge Hello World



Open your first issue

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@AdarshRise leveled up to Apprentice
The world is no longer new and the training wheels have been removed. You’ve proven your dedication to the cause, yet have much to learn. Press on, faithful apprentice!