Add missed mock generator for static fields

[CaelmBleidd]

Description

This request adds two missed generators for mocks that led to unexpected unsat results.
It happened because when a static variable was on a right side of an assignment, it was created with the corresponding mock generator. Then, if some other variable related to the same class would be encountered on the left side of the assignment, it was created without such a generator, which led to a contradiction between isMock values in these two scenarios.

There was one more missed generated related to final statics: when we reset statics, we should provide a corresponding mock generator.

Type of Change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Regression and integration tests

The same as automatic tests.

Automated Testing

org.utbot.examples.mock.MockStaticFieldExampleTest#testCheckMocksInLeftAndRightAssignPartFinalField
org.utbot.examples.mock.MockStaticFieldExampleTest#testCheckMocksInLeftAndRightAssignPart

Manual Scenario

There is no specific manual scenario.

Checklist:

• The change followed the style guidelines of the UTBot project
• Self-review of the code is passed
• The change contains enough commentaries, particularly in hard-to-understand areas
• New documentation is provided or existed one is altered
• No new warnings
• New tests have been added
• All tests pass locally with my changes