Fix minor spelling error in What's new for Python 3.8 (GH-14371)

diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst
index 1177c82..a0c881a 100644
--- a/Doc/whatsnew/3.8.rst
+++ b/Doc/whatsnew/3.8.rst
@@ -1508,7 +1508,7 @@
 * The :opcode:`MAP_ADD` now expects the value as the first element in the
   stack and the key as the second element. This change was made so the key
   is always evaluated before the value in dictionary comprehensions, as
-  porposed by :pep:`572`. (Contributed by Jörn Heissler in :issue:`35224`.)
+  proposed by :pep:`572`. (Contributed by Jörn Heissler in :issue:`35224`.)
 
 
 Demos and Tools