Fix test failure on Windows due to NamedTemporaryFile behavior

[denini08]

Hello. While running the tests on Windows, I encountered a PermissionError caused by how tempfile.NamedTemporaryFile behaves on this platform. On Windows, temporary files created with NamedTemporaryFile cannot be reopened while still open, unlike on Unix-based systems.

To make the test portable across platforms, I modified the fixture to:

• Use delete=False so the file can be reopened.
• Close the file before using it in the test.
• Explicitly delete the file after the test finishes.

This ensure the test works consistently on both Windows and Linux/macOS.

[davidsbatista]

Hi @denini08! Thanks for this 👍🏽