Trying to markdown embed code in a MR, using a forked branch

[roboticswithjulia]

Hello,
I am trying to use the markdown-embed-code in the ros2-rust package to write examples.
But, when trying to make the MR, the action does not build because the actions/checkout is trying to find a branch that it does not exist in the repository as it is created in the forked repository.
Here is the issue: https://github.com/ros2-rust/ros2_rust/actions/runs/14225257519/job/39863151430?pr=467#step:4:77
Also I tried to execute the default example and it does not work: https://github.com/roboticswithjulia/ros2_rust/actions/runs/14230316793/job/39879409797?pr=2 I get this error:
fatal: --local can only be used inside a git repository

Any idea how to make a checkout to a branch created in the forked and to make this work in the actions of the MR? Before merging to Master? And also, how to make the default example work?

Thank you so much for your help and assistance!

Júlia