chore(deps): bump simple-git and lint-staged

Removes [simple-git](https://github.com/steveukx/git-js/tree/HEAD/simple-git). It's no longer used after updating ancestor dependency [lint-staged](https://github.com/okonet/lint-staged). These dependencies need to be updated together.


Removes `simple-git`

Updates `lint-staged` from 8.2.1 to 15.0.2
- [Release notes](https://github.com/okonet/lint-staged/releases)
- [Changelog](https://github.com/lint-staged/lint-staged/blob/master/CHANGELOG.md)
- [Commits](lint-staged/lint-staged@v8.2.1...v15.0.2)

---
updated-dependencies:
- dependency-name: simple-git
  dependency-type: indirect
- dependency-name: lint-staged
  dependency-type: direct:development
...

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