Enhancement: replace engine for tests

[Ilya-Green]

Is your feature request related to a problem? Please describe.
I want to make tests for my app but i want to replace databse engine from main app class

Describe the solution you'd like
Is there any option to make pytest from admin class but set another databse to this class?

Describe alternatives you've considered
Rewriting and recreating a class in every test can take a very long time and may be not secure. Making any changes to the main application will require rewriting this every time in every test.