docs: protected String createFormFieldName(BinaryAttachment binaryAttachment) {
      if (binaryAttachment.getFieldName() != null) {
        return binaryAttachment.getFieldName();
      }
  
      String name = binaryAttachment.getFilename();
      int fileExtensionIndex = name.lastIndexOf('.');
      return fileExtensionIndex > 0 ? name.substring(0, fileExtensionIndex) : name;
    }