Fix missing imports in sample code in README

Taken from [pull/561](#561) on main repo.
googlesamples · Dec 21, 2023 · da0779a · da0779a
1 parent f29320b
commit da0779a
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/README.md b/README.md
@@ -335,6 +335,10 @@ In order to modify the generated Podfile you can create a script like this:
 ```csharp
 using System.IO;
 
+using UnityEditor;
+using UnityEditor.Callbacks;
+using UnityEngine;
+
 public class PostProcessIOS : MonoBehaviour
 {
     // Must be between 40 and 50 to ensure that it's not overriden by Podfile generation (40) and