[mypy] Fix type annotations for graphs/boruvka (#4867)
[mypy] Fix type annotations for graphs/boruvka (#4867)

* fix: type annotations for pypi 🏷️

Fixes #4052

* updating DIRECTORY.md

* apply suggestions from code review

Co-authored-by: Christian Clauss <585dd401264c1e46d17ebec1862e5d2a9b6a6c5d@me.com>

Co-authored-by: github-actions <47a35b99ddbe74edbea9dad62cf9a3b212194173@users.noreply.github.com>
Co-authored-by: Christian Clauss <585dd401264c1e46d17ebec1862e5d2a9b6a6c5d@me.com>
TheAlgorithms/Python