fix: patch LocalSourceFile to work with containerize

[mfansler]

Description

Fixes #1210 by implementing the os.PathLike interface (__fspath__()). Updates interface usage. Adds test to demonstrate fix.

QC

• The PR contains a test case for the changes or the changes are already covered by an existing test case.
• The documentation (docs/) is updated to reflect the changes or this is not necessary (e.g. if the change does neither modify the language nor the behavior or functionalities of Snakemake).

[mfansler]

@johanneskoester please let me know if you'd like a different direction for this. I realized after submitting that we don't need to add __fspath__ to LocalSourceFile, but could instead just modify all the env.file references to env.file.get_path_or_uri(). Personally, I think it makes semantic sense for LocalSourceFile to implement os.PathLike, unless one can imagine a local source file without a path.

[johanneskoester]

Thank you!

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

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0.0% Duplication

[johanneskoester]

I have some additional related fixes in #1236. Thanks a lot for your work here, I've integrated it into the other PR (I will reference you in the release notes).