How to test async actions

It would be great to add an example in the docs on how to test async actions with data sources and check that success and error actions are dispatched appropriately.

I'm struggling to grasp how to best do that and the current one example for testing actions is a little simple

Review the existing action-testing example in the documentation, then trace how async actions use data sources. Add an example that checks both success and error actions are dispatched, and verify that it addresses the gap described in the issue.

Written by the indexing model from the issue text.