gh-113329: Catch OSError in doctest finder and document that inspect.getsourcefile/getfile can raise OSError

[stenwessel]

Fixes #113329, which occurs when running doctests in a class docstring in a REPL environment. Since Python 3.10, an OSError is raised when the class source code cannot be found.

Just as inspect.getsourcelines, this PR adds documentation for inspect.getsourcefile and inspect.getfile that it can raise an OSError when the source code cannot be found.

Additionally, this PR now also catches OSError in the doctest finder. The source code is only necessary to discover line numbers, and is already ignored when a TypeError occurs. This restores behavior from CPython version < 3.10 where doctests can be found on a class object in the REPL (and, in particular, also in notebook environments).

• Issue: Running doctest examples on a class results in OSError in REPL #113329

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Documentation build overview

📚 cpython-previews | 🛠️ Build #34018886 | 📁 Comparing 7a9e7bb against main (3444ef9)

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2 files changed

± library/inspect.html
± whatsnew/changelog.html