ENH: Add serialization for incremental linear models

[olegkkruglov]

Description

• Added __getstate__ method to IncrementalLinearRegression and IncrementalRidge
• Removed redundant check for onedal table backend in onedal/datatypes/data_conversion.cpp. It is necessary because partial result for linear models contains column-major tables on C++ side. Serialization tests confirm conversion actually works well for column-major tables as well.
• 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
• Updated deselected_tests.yaml

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[icfaust]

/intelci: run

[david-cortes-intel]

Since this note will appear in multiple classes, perhaps it could be moved into a common variable and the docstrings modified programmatically for all the classes that will have the note.

[olegkkruglov]

It is good idea. I think it could be done in a separate PR moving some common things for all incremental algorithms to separate classes/variables.