Update dependency rector/rector to v2.1.6

Author: renovate[bot]

api/composer.json

@@ -69,7 +69,7 @@
         "phpspec/prophecy-phpunit": "2.4.0",
         "phpstan/phpstan": "2.1.22",
         "phpunit/phpunit": "12.3.8",
-        "rector/rector": "2.1.5",
+        "rector/rector": "2.1.6",
         "psalm/phar": "6.13.1",
         "spatie/phpunit-snapshot-assertions": "5.2.2",
         "symfony/browser-kit": "7.3.2",