Tools - rector (deps-dev): bump rector/rector in /tools/rector (#243)

Bumps [rector/rector](https://github.com/rectorphp/rector) from 2.1.6 to 2.1.7.
- [Release notes](https://github.com/rectorphp/rector/releases)
- [Commits](rectorphp/rector@2.1.6...2.1.7)

---
updated-dependencies:
- dependency-name: rector/rector
  dependency-version: 2.1.7
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

tools/rector/composer.json

@@ -1,5 +1,5 @@
 {
     "require-dev": {
-        "rector/rector": "^2.1.6"
+        "rector/rector": "^2.1.7"
     }
 }