Wrong formatting in hugin script

[Yurivanderburg]

Hi there!

I think I found a typo in one of the lua scripts (see screenshots). The formatting for the total number of images to be exported was wrong, I think. Changing the '$' to '%' fixed the issue for me.

https://github.com/darktable-org/lua-scripts/blob/a9191cf084ea7c223d0c18504f17043ad973eff3/contrib/hugin.lua#L86C54-L86C55