[clang] [libclang/python] Fix bug in `SourceRange.__contains__`, add tests (PR #101802)

[Jannick Kremer via cfe-commits]

================
@@ -65,6 +65,9 @@ Clang Python Bindings Potentially Breaking Changes
 - Calling a property on the ``CompletionChunk`` or ``CompletionString`` class
   statically now leads to an error, instead of returning a ``CachedProperty`` object
   that is used internally. Properties are only available on instances.
+- For a single-line ``SourceRange`` and a ``SourceLocation`` in the same line,
----------------
DeinAlptraum wrote:

Thanks for the reviews, and added 👍🏼 

https://github.com/llvm/llvm-project/pull/101802