Extend third party tests

[antonwolfy]

The PR includes

• migration of some tests from unittest to pytest
• updates in FFT tests
• new tests for random.choice

This PR is intended to reflect alignment with the recent changes in origin repo of third party tests.

• Have you provided a meaningful PR description?
• Have you added a test, reproducer or referred to an issue with a reproducer?
• Have you tested your changes locally for CPU and GPU devices?
• Have you made sure that new changes do not introduce compiler warnings?
• Have you checked performance impact of proposed changes?
• Have you added documentation for your changes, if necessary?
• Have you added your changes to the changelog?

[github-actions]

View rendered docs @ https://intelpython.github.io/dpnp/pull/2727/index.html

[github-actions]

Array API standard conformance tests for dpnp=0.20.0dev1=py313h509198e_52 ran successfully.
Passed: 1229
Failed: 0
Skipped: 7

[coveralls]

coverage: 81.337%. remained the same
when pulling 8f8a1f9 on update-cupy-tests
into 96bb408 on master.