Check type of input in `dpnp.repeat` to raise a proper validation exception if any

[antonwolfy]

That PR proposes to add an explicit type check of input array to dpnp.repeat.

Before the change there was the exception raised about missing ndim attribute for scalar input. The issue come from the comment.

Also the docstring description was updated with more details about supported input arguments. And more tests scenario were added to cover missing use cases.

• [x] Have you provided a meaningful PR description?
• [ ] Have you added a test, reproducer or referred to issue with a reproducer?
• [x] Have you tested your changes locally for CPU and GPU devices?
• [x] 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?

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