Reorder the list of argparse experts in alphabetical order. (#1599)

Author: serhiy-storchaka

core-developers/experts.rst

@@ -56,7 +56,7 @@ __future__
 __main__              gvanrossum, ncoghlan
 _thread
 abc
-argparse              serhiy-storchaka*, savannahostrowski*
+argparse              savannahostrowski*, serhiy-storchaka*
 array
 ast                   benjaminp, pablogsal, isidentical, JelleZijlstra, eclips4
 asyncio               1st1, asvetlov, gvanrossum, graingert, kumaraditya303, willingc