Fix cs/stan

[o0h]

This pull request updates several test methods to improve clarity and consistency in naming conventions for data providers and their return types. The changes primarily involve renaming data provider methods and adding type annotations to enhance readability and maintainability.

Updates to data providers:

• tests/unit/Differ/DiffCollectorTest.php: Renamed the data provider method getPhpDiffsAstChangedProvider to provideGetPhpDiffsAstChangedCases and added a type annotation specifying the return type as iterable<array{int, bool, GitInterface, DiffFactory}>. [1] [2]
• tests/unit/Differ/DiffFactoryTest.php: Renamed the data provider method createForPhpProvider to provideCreateForPhpCases and added a type annotation specifying the return type as iterable<array{GitStatus, ?string, ?string}>. [1] [2]