Give an abi3t example

Author: stefanor

Doc/whatsnew/3.16.rst

@@ -82,7 +82,8 @@ Other language changes
   (Contributed by Łukasz Langa in :gh:`102960`.)
 
 * Stable ABI extensions may now include a multiarch tuple in the
-  filename, e.g. ``foo.abi3-x86-64-linux-gnu.so``.
+  filename, e.g. ``foo.abi3-x86-64-linux-gnu.so`` and
+  ``foo.abi3t-aarch64-linux-gnu.so``.
   This permits stable ABI extensions for multiple architectures to be
   co-installed into the same directory, without clashing with each
   other, as regular dynamic extensions do. Build tools will generate