Fix bug with notification HTML (#11827)

Noticed this polling the notification HTML tags we're depending on

readthedocs/config/notifications.py

@@ -154,7 +154,7 @@
         body=_(
             textwrap.dedent(
                 """
-            The name of the package <code>{{pacakge}}</name> is invalid.
+            The name of the package <code>{{pacakge}}</code> is invalid.
             """
             ).strip(),
         ),