build(deps-dev): update rector/rector requirement from 0.19.5 to 0.19.8

Updates the requirements on [rector/rector](https://github.com/rectorphp/rector) to permit the latest version.
- [Release notes](https://github.com/rectorphp/rector/releases)
- [Commits](rectorphp/rector@0.19.5...0.19.8)

---
updated-dependencies:
- dependency-name: rector/rector
  dependency-type: direct:development
...

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

composer.json

@@ -32,7 +32,7 @@
         "phpstan/phpstan": "^1.10",
         "phpunit/phpcov": "^8.2",
         "phpunit/phpunit": "^9.6",
-        "rector/rector": "0.19.5"
+        "rector/rector": "0.19.8"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,