Add unit tests for VirtualizedList render quirks (#31401)

Summary:
This change adds a series of snapshot tests to validate the render output of VirtualizedList in mixed scenarios. Jest timer mocks are used to measure rendering at different ticks. These test cases mostly center around realization logic, to help prevent regressions when chaning internal state representation.
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[Internal] [Added] - Add unit tests for VirtualizedList render quirks

Pull Request resolved: #31401

Test Plan: Ran the added UTs locally.

Reviewed By: lunaleaps

Differential Revision: D28017750

Pulled By: rozele

fbshipit-source-id: df9684c4ac80a8732f3e88e7496815127213832e

Author: NickGerleman