Add pod stats - Githubissues

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This pull request fixes #4 and includes the following tasks.

GitHub Actions are used to create a new automation in .github/workflows/leaderboard-count.yml. It updates the fellows.yml file by incrementing a particular fellow's contributions each time code is pushed into the repository. The contributions key in fellows.yml must not be reset or updated by other commits to ensure that it works as expected.

A leaderboard has been created in _includes/leaderboard.html to display the names and number of contributions of fellows in descending order of contributions.

MLH-Fellowship / march-2022-prep-portfolio

Add pod stats #24

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