chore(deps-dev): bump flake8-isort from 4.2.0 to 6.0.0

Bumps [flake8-isort](https://github.com/gforcada/flake8-isort) from 4.2.0 to 6.0.0.
- [Release notes](https://github.com/gforcada/flake8-isort/releases)
- [Changelog](https://github.com/gforcada/flake8-isort/blob/master/CHANGES.rst)
- [Commits](gforcada/flake8-isort@4.2.0...6.0.0)

---
updated-dependencies:
- dependency-name: flake8-isort
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>