bpo-35044, doc: Use the :exc: role for the exceptions (GH-10037)

diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 83aee1b..b35a724 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -1161,7 +1161,7 @@
       If *delta* is supplied instead of *places* then the difference
       between *first* and *second* must be less or equal to (or greater than) *delta*.
 
-      Supplying both *delta* and *places* raises a ``TypeError``.
+      Supplying both *delta* and *places* raises a :exc:`TypeError`.
 
       .. versionchanged:: 3.2
          :meth:`assertAlmostEqual` automatically considers almost equal objects