Fix UdonSharp compile errors when Unity project contains editor scripts with namespace `****.Editor`.

[shivaduke28]

This PR fixes: UdonSharp shows a compile error:

[UdonSharp] Assets/USharpVideo/Scripts/UI/UIStyler.cs(155,37): error CS0118: 'Editor' is a namespace but is used like a type

when there is an editor script with a namespace ****.Editor. This happens even when that editor script belongs to an asmdef with auto referenced disabled.