UTBot Python updates from SBFT version

[tamarinvs19]

Description

Refactoring and new features form SBFT branch:

• prepared structure to use symbolic execution
• supported iterators in fuzzing and codegen
• supported @staticmethod decorator
• refactored cli interface: arguments, cancellation, parsing
• new timeout separation between testing elements
• improved type inference and generic substitutions
• improved fuzzing for typing.Any annotations

How to test

Automated tests

Run utbot-python/samples/run_all_tests.sh and check COVERAGE_REPORT

Self-check list

Check off the item if the statement is true. Hint: [x] is a marked item.

Please do not delete the list or its items.

• [x] I've set the proper labels for my PR (at least, for category and component).
• [x] PR title and description are clear and intelligible.
• [x] I've added enough comments to my code, particularly in hard-to-understand areas.
• [x] The functionality I've repaired, changed or added is covered with automated tests.
• [ ] Manual tests have been provided optionally.
• [x] The documentation for the functionality I've been working on is up-to-date.