Core tests to be running within github actions

[antonwolfy]

The PR proposes to add third party core tests for ndarray to the scope of public CI, as part of Conda package action.
While the scope of core tests is extended with ones for unary ndarray operations.

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• Have you added a test, reproducer or referred to 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?
• If this PR is a work in progress, are you filing the PR as a draft?

[github-actions]

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