Cannot move paired notebook to newly created sub-directory

[lucas-bremond]

Using a global configuration like this one:

formats = "notebooks///ipynb,scripts///py:percent"

and moving a notebook stored under ./notebook/my_notebook.ipynb to a newly created ./notebook/subdir directory (so that the destination would be ./notebook/subdir/my_notebook.ipynb) fails when subdir is not already present under ./scripts/.