Port API tests in module test_permission

Subsume module `test_permission` into module `test_permission_v2`. Make the
relevant tests use the new API testing tools, not the old API testing tools.

Fix #1447.
The `attributes` method could probably be used here. However, I'm hoping to trash `EntityFactoryMixin` and make an `EntityCreateMixin` at some point. Merely updating the name provies that an update is possible, which is the point of the test.