Add implementation of `dpnp.frexp`

[antonwolfy]

The PR adds the implementation of dpnp.frexp and extends the framework to support a unary function with two output arrays, including new wrappers in ufunc pybind11 extension and new python class DPNPUnaryTwoOutputsFunc.

• [x] Have you provided a meaningful PR description?
• [x] Have you added a test, reproducer or referred to an 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?
• [x] Have you added documentation for your changes, if necessary?
• [x] Have you added your changes to the changelog?

[github-actions[bot]]

View rendered docs @ https://intelpython.github.io/dpnp/pull/2635/index.html

[coveralls]

coverage: 81.397% (-0.1%) from 81.511% when pulling 9a707acdb202fa83733c8586f0a2216463b1688f on impl-frexp into 6b8ea9e2bdd30bfcd12694e4a02c0288ba20b5f3 on master.

[github-actions[bot]]

Array API standard conformance tests for dpnp=0.20.0dev0=py313h509198e_58 ran successfully. Passed: 1227 Failed: 0 Skipped: 9