Add example custom simulator

[currocam]

Add custom simulator example to documentation

Hi,
A few weeks ago, we added the feature of passing a custom simulator function in #44. I've added a minimal example in the documentation. I'm not sure how to run the docs CI, but the website looks good to me after building it with make local .

It was also mentioned (#44 (comment)) to add some examples on the Exploratory Analysis of Bayesian Models. I'm happy to help. I found that book very nice, actually.

[aloctavodia]

You can check the docs by going to the checks section in each PR and clicking on "docs/readthedocs.org:simuk — Read the Docs build succeeded!"

The example is fine, but it's kind of "hidden" inside the tab. We should add more structure. Something like

Simulation based calibration

This example demonstrates how to use the SBC class for simulation-based calibration, supporting PyMC, Bambi and Numpyro models.

Out-of-the-box SBC (or something else)

tabs

Custom simulator SBC (or something else)

tabs

[currocam]

Hi, yes, I agree. I've made the change.