Info about submodules

Hi, i need use multiple repo to build correctly some app with gitlab runner, I think it’s better to use git submodules, but maybe I did not understand how it works…
I have 2 repo:

To build repo1 i need some file of repo2, so into repo1 i put .gitmodules

[submodule "repo2"]
    path = repo2
    url = ../repo2.git

and .gitlab-ci.yml


When build the project, into logs i view Updating/initializing submodules recursively... (green) without errors, but not found any folder repo2 into workspace, it should be in /builds/group/repo1/repo2 (?) repo2.git is a private repo and have same permission of repo1
it’s right?