Last summer at the integrate summit I did a session on automated testing with Logic App Standard. The recording of it is here:
Since then I have done a bunch of additional work on the framework and been using it in the real world with some good success.
There is a load of documentation in the Integration Playbook about how to use the framework. The below image shows where it is and you can use this link:
https://www.integration-playbook.io/docs/integrate-summit
In the how to section I have a bunch of notes and videos on how to do some of the common task you might need to do when doing automated tests for logic apps.
There is also a youtube playlist for all of the videos here
The code for the logic app testing framework is here:
https://github.com/michaelstephensonuk/IntegrationPlaybook-LogicApp-Standard-Testing
There is a sample project showing most of the demos I show in the various videos which is available here:
https://github.com/michaelstephensonuk/IntegrationPlaybook-LogicApp-Standard-Testing-Example