Currently, I don’t know of a built-in option to push to Git. Here’s a video of what I have to do to push to Git/GitHub:
The Git plugin is third party:
UEGitPlugin is a simple Git Source Control Plugin for Unreal Engine
Written and contributed by Sebastien Rombauts (sebastien.rombauts@gmail.com)
Maybe try reaching out to Sebastien directly.
Or switch to Unreal Revision Control instead?