Bug in converting to MD step in tutorial

[msm1089]

I have followed the steps on the page https://www.fast.ai/2020/01/16/fast_template/, where you detail how to set up a blog etc. I've encountered what seems to be a bug - when using the command nbdev_nb2md test.ipynb the notebook itself is being modified. Specifically, any image markdown links do not work after the nbdev conversion process. I checked the notebook before running it and after, and can see that the attachments field has been removed during the conversion. Nothing else seems to have changed, so should be an easy fix if it is actually a bug?

If it is intentional tho, please could you consider this a feature request for the original notebook not to be changed when converting?