Importing a project from CE to GitLab.com fails with `"wrong argument type nil"` and no other explanation. ### Steps to reproduce 1. Export an existing projects (Settings -> Export project) and download the *.tar.gz 1. Create a new project on another server and choose "Import project from: GitLab export" 1. Choose the previously downloaded *.tar.gz and click on "Import project" ### Example Project Private project accessible through internal google drive. ### What is the current _bug_ behavior? After clicking on "Import project", the following error appears: ``` The repository could not be imported. Error importing repository into <PROJECTPATH> - wrong argument type nil ``` ### What is the expected _correct_ behavior? The project is imported successfully and contains all data as at the time the export was created. /cc @jameslopez