fixup! [clang] Ignore GCC 11 [[malloc(x)]] attribute

Fix incorrect RST link syntax.

Co-authored-by: Aaron Ballman <[email protected]>

Author: aloisklink

clang/docs/ReleaseNotes.rst

@@ -292,7 +292,7 @@ Bug Fixes to Attribute Support
 - Clang now emits a warning instead of an error when using the one or two
   argument form of GCC 11's ``__attribute__((malloc(deallocator)))``
   or ``__attribute__((malloc(deallocator, ptr-index)))``
-  (`#51607 <https://github.com/llvm/llvm-project/issues/51607>`).
+  (`#51607 <https://github.com/llvm/llvm-project/issues/51607>`_).
 
 Bug Fixes to C++ Support
 ^^^^^^^^^^^^^^^^^^^^^^^^