Support __setstate__ for custom state of python objects

[tamarinvs19]

Description

Supported serialisation and deserialsation of python objects that have custom states (e.g. have __slots__ with a list of valid attributes). For these objects we should use __reduce_ex__ method instead of __reduce__ to serialise if it is possible and then use custom method __setstate__ to deserialise state.

Changes in utbot-executor: tamarinvs19/utbot_executor#1

How to test

Automated tests

There are tests for serialization and deserialization processes in utbot-executor (utbot_executor/deep_serialization/tests.py)

Manual tests

See example utbot-python/samples/easy_samples/setstate_test.py

Expected: success test generation for make_my_class

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