Change test_array_backends mixin classes to subclass QiskitDynamicsTestCase

[DanPuzzuoli]

Summary

Changes the classes utilized by test_array_backends to be subclasses of QiskitDynamicsTestCase. The arraylias module tests have also been updated (this is the only test folder that currently uses this).

Details and comments

[to24toro]

A modification where Arraytest inherits QiskitDynamicsTestCase caused a no-member error in the existing tests that inherits QiskitDynamicsTestCase since the method of QiskitDynamicsTestCase is not found in the tests.(e.g. self.assertAllClose()). At least, I believe we have to acknowledge this error.

It might be good to provide a means of Arraylais to make tests for some arrays work.