Refactor test cases to simplify async context management and improve readability

[dcloud347]

This pull request updates the test suite to improve compatibility with pytest's asyncio support and simplifies the usage of test fixtures. The most important changes are the removal of unnecessary @pytest.mark.asyncio decorators and the refactoring of test fixture usage from asynchronous iteration to direct unpacking, making the tests cleaner and easier to read.

Pytest configuration improvements:

• Enabled automatic asyncio mode in pytest.ini by adding asyncio_mode = auto, ensuring better handling of async tests without explicit decorators.

Test fixture usage simplification:

• Refactored all tests using the neo4j_container_with_kg_fixture fixture to unpack the fixture directly (neo4j_container, kg = neo4j_container_with_kg_fixture) instead of using async for, streamlining test code and improving readability. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21]

Decorator cleanup:

• Removed unnecessary @pytest.mark.asyncio decorators from async test functions, relying on the new pytest configuration for async test support. [1] [2] [3]

Minor code formatting improvements:

• Simplified code formatting in test message lists and assertion blocks for clarity and consistency. [1] [2]

These changes collectively make the test suite easier to maintain and ensure proper execution of async tests with pytest.