ModelBuilder notebook is missing predicted regression lines

[fonnesbeck]

Using ModelBuilder class for deploying PyMC models:
https://www.pymc.io/projects/examples/en/latest/howto/model_builder.html:

Issue description

The last plot of the notebook, which is supposed to be predicted regression lines, currently only shows the data points:

[reshamas]

@BerylKanali is working on this with @Monsurat-Onabajo