git submodules

(this is bonus comic #2 for "How Git Works" https://wizardzines.com/zines/git, covering some topics I didn't talk about in the zine!)

@b0rk If you interrupt the process of cloning a submodule, you can end up with files missing, even if you try to update submodules again! HEAD will point to the correct commit but the staging area and working tree will not. git restore -SW . in the submodule should correct this