DX: rector in docs directory

docs/source/_static/code/exports/CountPerson.php

@@ -50,18 +50,9 @@ class CountPerson implements ExportInterface
     public function getLabels($key, array $values, $data)
     {
         // the Closure which will be executed by the formatter.
-        return function ($value) {
-            switch ($value) {
-                case '_header':
-                    // we have to process specifically the '_header' string,
-                    // which will be used by the formatter to show a column title
-                    return $this->getTitle();
-
-                default:
-                    // for all value, we do not process them and return them
-                    // immediatly
-                    return $value;
-            }
+        return fn($value) => match ($value) {
+            '_header' => $this->getTitle(),
+            default => $value,
         };
     }