ENH: Added serialization for IncrementalBasicStatistics

[olegkkruglov]

Description

• Added __getstate__ method to IncrementalBasicStatistics
• Finalization is called with serialization during __getstate__ method
• _need_to_finalize flag is added to avoid unnecessary call of finalization backend.
• Added test for checking if it works well

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Performance

• [x] I have measured performance for affected algorithms using scikit-learn_bench and provided at least summary table with measured data, if performance change is expected.
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[olegkkruglov]

/intelci: run

[olegkkruglov]

/intelci: run

[david-cortes-intel]

LGTM, provided the test failures are fixed.

[olegkkruglov]

/intelci: run