need unit test without any graphical user interface

[SebG-js]

Is your feature request related to a problem? Please describe.
I have integrated my teams bot to a python fast api.

Describe the solution you'd like
I would like to define unit tests (pytest) to test "api/messages" when an user posts a new text message,
without any graphical user interface,
with a simple method,
without any connection to an external server.
The target is to test my code in a cicd pipeline, without any human action.

Describe alternatives you've considered
How to deactivate the authentification ?

Additional context
Add any other context or screenshots about the feature request here.