Add unit tests for config

**Feature request**
It would be great to have monitoring for models.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_monitoring` with default `false`.

Start by locating the configuration handling and existing unit tests for config options. Confirm where the default is defined and how options are read; done means enable_monitoring defaults to false and tests cover that behavior.

Written by the indexing model from the issue text.