Adapt beluga_tutorial code to key concepts

[Alondruck]

Proposed changes

Adapt the main code to the names used by the key concepts.

Type of change

• 🐛 Bugfix (change which fixes an issue)
• 🚀 Feature (change which adds functionality)
• 📚 Documentation (change which fixes or extends documentation)

Checklist

• Lint and unit tests (if any) pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• All commits have been signed for DCO

Additional comments

This PR will wait for #390 to be merged into the main branch.

[Alondruck]

@nahueespinosa @hidmic I realized that we are not using the default values of the Parameters struct. Should we use them, or is it fair to require the user to provide a path to the parameters file?

In the explanation of the tutorial, I'll delete all the code related to YAML, and the user will use the default parameters. So, I want to know your thoughts on whether we also need to let the user use the default parameters here.

[nahueespinosa]

I want to know your thoughts on whether we also need to let the user use the default parameters here.

No strong opinion on this one. We could make the parameter_path argument optional, loading the default values if no yaml file is provided, but I also don't mind that we always ignore the default values.

[nahueespinosa]

LGTM!