Authenticate Azure Repositories in Pipelines

Hi,

I'm trying to use Julia's LocalRegistry with Azure DevOps.

LocalRegistry is basically a Git Repository with references to other Git repositories.

In Azure DevOps I can checkout additional repositories using the following syntax: 

resources:
 repositories:
 - repository: ProjectA
   type: git
   name: ProjectA/GitA
(...)
- checkout: ProjectA

However, Julia's LocalRegistry just uses the direct git repo URL and uses an internal git manager to pull the repo and find references. So, per design, I don't use the checkout-feature from DevOps but let Julia clone the Git repo internally.

For this step, I can just put a PAT (and here, the SystemAccessToken is not working for me?), put it in the Git-Repo URL and use this for the LocalRegistry.

However, I can't include a PAT into the Git-URL-References on the Registry Repo. Thus, Julias LocalRegistry can successfully obtain a copy of the current index, but it fails when it comes to actually pull other projects using the Package Manager with the following error message: 

 error: GitError(Code:EUSER, Class:Callback, Aborting, user cancelled credential request.)

What could I do here? How can I add the required credentials?