python tests suite fails on windows

[reyammer]

The tests suite at https://github.com/google/magika/blob/main/.github/workflows/python-test-suite.yml somehow fails when running it on windows.

Some of the failures are about mypy (rightfully) complaining about the signal module, but even when commenting that out, other issues pop out when running the tests. These include some misdetection-related checks, which is very weird as nothing should change depending on the operating system.

[ps2181]

@reyammer Could the issue be related to how the OS handles line ending differences (\r\n vs. \n), case sensitivity in paths, or encoding mismatches if files aren’t explicitly set to UTF-8? For any tests involving path comparisons, using os.path.normcase() might help ensure consistency across platforms.