gh-117084: Fix zip extraction bug

[fliiiix]

On Windows a directory is ending in \ and not /.

This is the smallest fix i could think of.
Not sure if there are edge cases with files containing \\ at the end.

• Issue: Zip extract fails for zips created with Windows #117084

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[serhiy-storchaka]

Thank you for your contribution @fliiiix. I have two requirements:

• It should not change the behavior on non-Windows platforms by default. The logic should match the logic of the extraction code.
• Tests are required.

Creating specific tests is something non-trivial task, so instead of guiding you to find the right solution (which I myself didn't know at first), it was easier for me to do it myself (#117129). Anyway, thank you. I hope for fruitful cooperation in the future.

[fliiiix]

so instead of guiding you to find the right solution

Did you just denied my first contribution to cpython? 😢

[serhiy-storchaka]

I'm sorry. But now that you've taken the first steps, cloned the repository, and created your first PR, creating other PRs should be much easier, so I look forward to your contribution in the future.