Solving the `Top k most frequent words` problem using a max-heap (#8685)

* Solving the `Top k most frequent words` problem using a max-heap

* Mentioning Python standard library solution in `Top k most frequent words` docstring

* ruff --fix .

* updating DIRECTORY.md

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Co-authored-by: Amos Paribocci <aparibocci@gmail.com>
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>