remove unused extension that uses FlutterError

 import AVFoundation
-import Flutter
 import Foundation
 import MLKitBarcodeScanning
 
-extension Error {
-    func throwNative(_ result: FlutterResult) {
-        let error = FlutterError(code: localizedDescription, message: nil, details: nil)
-        result(error)
-    }
-}
-
 extension CVBuffer {
     var image: UIImage {
         let ciImage = CIImage(cvPixelBuffer: self)