[clang] [libclang/python] Fix get_exception_specification_kind (PR #101548)

[Vlad Serebrennikov via cfe-commits]

Endilll wrote:

> @Endilll I found another bug on the way, so here's a fix+test. Does this need a release note under `Python Binding Changes`?

Yes, the general approach is that every change should come with a test and a release note.

On a different note, I wonder if there's a way to prevent this kind of bugs. Seems quite unfortunate that our python binding might not work because of something this silly.

https://github.com/llvm/llvm-project/pull/101548