Errors found in `manage_python_project` notebook

[despadam]

Give more information on how to execute git commands when someone has two factor authentication in Github. Someone with 2fa could not even clone the repo inside Renku

[edoardob90]

We should tell them to modify the origin URL with the following command to avoid the prompt of user/token every single time:

git remote set-url origin https://USERNAME:TOKEN@github.com/USERNAME/mypackage.git