How to fix this error when i build project
(ArgumentException: The Assembly UnityEditor is referenced by StoryBookEditor ('Assets/Scripts/StoryBookEditor.dll'). But the dll is not allowed to be included or could not be found.
UnityEditor.AssemblyHelper.AddReferencedAssembliesRecurse (System.String assemblyPath, System.Collections.Generic.List`1[T] alreadyFoundAssemblies, System.String[] allAssemblyPaths, System.String[] foldersToSearch, System.Collections.Generic.Dictionary`2[TKey,TValue] cache, UnityEditor.BuildTarget target) (at C:/buildslave/unity/build/Editor/Mono/AssemblyHelper.cs:150)
UnityEditor.AssemblyHelper.FindAssembliesReferencedBy (System.String[] paths, System.String[] foldersToSearch, UnityEditor.BuildTarget target) (at C:/buildslave/unity/build/Editor/Mono/AssemblyHelper.cs:190)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)
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