[#12048] Migrate Tests for DeleteStudentActionTest

[DhiraPT]

Part of #12048

Outline of Solution
Migrated DeleteStudentActionTest to use SQL-based logic instead of the previous Datastore model.

[github-actions]

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[dishenggg]

Nice work! Sorry for late review just a few small changes

[dishenggg]

I think that expanding the arguments that this verify checks for would be good, since in this case the deleteStudentCascade method should not be called at all, for example using

verify(mockLogic, never()).deleteStudentCascade(any(), any());

would ensure that the method is never called at all

[dishenggg]

For nonExistentStudentId and courseDoesNotExist, since deleteStudentCascade is actually called with some input.

I think that it might be better to verify that the method is called only once with "RANDOM_STUDENT" and verify that the method is never called again or with no other arguments

small nit: while we are here lets choose one of nonExistent... or ...DoesNotExist

[dishenggg]

Seems like I was a bit confused with when the logic is called, but you got the idea!

Just one more minor change

[dishenggg]

I think that setting this to

verify(mockLogic, times(1)).deleteStudentCascade(any(), any());

might be better here to ensure that the action doesnt delete some random student by accident because chances are if something does go wrong it might call the method with something else than the email you defined in BeforeMethod