I have an Xcode project where I'm using Git(Git Tower) as my version control, my issue is that Git Towershow uncommitted changes even after, committing all changes, closing the Xcode project and reopening it.
In other words, If I cleaned up my Staging area by committing all changes, then close the Xcode project; at this point, nothing has changed, the staging area is cleaned, but as soon as I re-open the Xcode project, Git Tower shows uncommitted changes in some .storyboard files without me doing anything to the views.
Any idea why Git shows uncommitted changes for some .storyboard files without me modifying anything, what is generating those changes in Xcode?
For instance, these changes showed up after committing all changes and reopening the project in Xcode.
EDIT:
My main question is why am I seeing uncommitted changes without me modifying anything, what is generating these changes in Xcode?

You might want to mark the file as "Assume Unchanged".
You can find more information on this in the Tower Help guide:
For more info on the difference between Ignoring a file and marking it as "Assume Unchanged" see our Help: https://www.git-tower.com/help/mac/working-copy/ignore-files