Update dependency phpunit/phpunit to ^11.5.56 (#354)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

composer.json

@@ -31,7 +31,7 @@
         "drupal/coder": "^8.3.31",
         "ergebnis/composer-normalize": "^2.52.0",
         "phpstan/phpstan": "^2.2.5",
-        "phpunit/phpunit": "^11.5.55",
+        "phpunit/phpunit": "^11.5.56",
         "pyrech/composer-changelogs": "^2.2",
         "rector/rector": "^2.5.4"
     },