I have our main project is in gitlab, so we are creating pipeline in gitlab only.
But, as a dependent project, one of our project is in github, which need to be cloned/download to the working directory and use those files.
The statements in the script section of your CI config are just Bash statements, so anything you can do on the command line, you can do in the pipeline.
First you need to ensure that your runner or image has Git installed, then you’ll need some sort of token in your CI env vars (masked!). Then you can probably do something like: