build(deps-dev): Bump rector/rector from 2.3.8 to 2.3.9 in /vendor-bin/rector in the dependencies group (#1200)

Bumps the dependencies group in /vendor-bin/rector with 1 update: [rector/rector](https://github.com/rectorphp/rector).


Updates `rector/rector` from 2.3.8 to 2.3.9
- [Release notes](https://github.com/rectorphp/rector/releases)
- [Commits](rectorphp/rector@2.3.8...2.3.9)

---
updated-dependencies:
- dependency-name: rector/rector
  dependency-version: 2.3.9
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

Author: dependabot[bot]