[Php81] Skip no type param on ReadOnlyPropertyRector (#1365)

* [Php81] Skip no type param on ReadOnlyPropertyRector

* fix

rules-tests/Php81/Rector/Property/ReadOnlyPropertyRector/Fixture/skip_no_type_param.php.inc

@@ -0,0 +1,22 @@
+<?php
+
+namespace Rector\Tests\Php81\Rector\Property\ReadOnlyPropertyRector\Fixture;
+
+final class SkipNoTypeParam
+{
+    /**
+     * @param mixed $data
+     */
+    public function __construct(
+        private $data
+    ) {
+    }
+
+    /**
+     * @return mixed
+     */
+    public function getData()
+    {
+        return $this->data;
+    }
+}

rules/Php81/Rector/Property/ReadOnlyPropertyRector.php

@@ -116,6 +116,10 @@ private function refactorParam(Param $param): Param | null
             return null;
         }
 
+        if ($param->type === null) {
+            return null;
+        }
+
         // promoted property?
         if ($this->propertyManipulator->isPropertyChangeableExceptConstructor($param)) {
             return null;