↓こんな感じのエラーが出た時は、
Cannot subscript a value of type '[String : Any]' with an index of type 'UIImagePickerController.InfoKey'
NG
private func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) { let image = info[UIImagePickerControllerOriginalImage] as! UIImage
OK
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) { let image = info[.originalImage] as! UIImage