Fix indentation in readme example

Author: ADmad

README.md

@@ -91,9 +91,9 @@ $this->Invoices->duplicate(4);
 Sometimes you need to access the original entity, e.g. for setting an ancestor/parent id reference.
 In this case you can leverage the `$original` entity being passed in as 2nd argument:
 ```php
-            'set' => [
-                'ancestor_id' => function ($entity, $original) {
-                    return $original->id;
-                },
-            ],
+'set' => [
+    'ancestor_id' => function ($entity, $original) {
+        return $original->id;
+    },
+],
 ```