Minor, adding headers. Fixes compile error in non-unity builds

Signed-off-by: Gene Walters <[email protected]>

Author: AMZN-Gene

Code/Framework/AzToolsFramework/AzToolsFramework/Prefab/Spawnable/AssetPlatformComponentRemover.h

@@ -9,6 +9,8 @@
 #pragma once
 
 #include <AzCore/Memory/SystemAllocator.h>
+#include <AzCore/std/containers/map.h>
+#include <AzCore/std/containers/set.h>
 #include <AzToolsFramework/Prefab/Spawnable/PrefabProcessor.h>
 
 namespace AZ