Silence another "default role used" warning in typing.rst

This should make ware-docs green again.
diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst
index 6993b31..d797aec 100644
--- a/Doc/library/typing.rst
+++ b/Doc/library/typing.rst
@@ -86,7 +86,7 @@
 ``UserId`` wherever an ``int`` might be expected, but will prevent you from
 accidentally creating a ``UserId`` in an invalid way::
 
-   # `output` is of type `int`, not `UserId`
+   # 'output' is of type 'int', not 'UserId'
    output = UserId(23413) + UserId(54341)
 
 Note that these checks are enforced only by the static type checker. At runtime