[Gimp-docs] typo

[Leedus McClein <leedusmcclein gmail com>]

In https://www.gimp.org/tutorials/Automate_Editing_in_GIMP/#trees-and-xml-data

"This lends a lot of flexibility with the way we structure of the data."

I think you meant to write:

"This lends a lot of flexibility with the way we structure the data."