[3.13] gh-132608: Fix a sample code coloring for ast.While (GH-132609) (#132612)

Author: miss-islington

Doc/library/ast.rst

@@ -1185,7 +1185,7 @@ Control flow
 
    .. doctest::
 
-        >> print(ast.dump(ast.parse("""
+        >>> print(ast.dump(ast.parse("""
         ... while x:
         ...    ...
         ... else: