[NFC][libclang/python] Fix code highlighting in release notes (#102807)

This corrects a release note introduced in #98745

Author: DeinAlptraum

clang/docs/ReleaseNotes.rst

@@ -61,9 +61,9 @@ Clang Frontend Potentially Breaking Changes
 Clang Python Bindings Potentially Breaking Changes
 --------------------------------------------------
 - Parts of the interface returning string results will now return
-  the empty string `""` when no result is available, instead of `None`.
-- Calling a property on the `CompletionChunk` or `CompletionString` class
-  statically now leads to an error, instead of returning a `CachedProperty` object
+  the empty string ``""`` when no result is available, instead of ``None``.
+- 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.
 
 What's New in Clang |release|?