AUTHORS: Update Don Stewart's e-mail address.

[ci skip]

.mailmap

@@ -34,6 +34,7 @@ David Himmelstrup           <lemmih@gmail.com>
 David Luposchainsky         <dluposchainsky@gmail.com>             <quchen@users.noreply.github.com>
 David Waern                 <davve@dtek.chalmers.se>               David Waern <unknown>
 Dennis Gosnell              <cdep.illabout@gmail.com>
+Don Stewart                 <dons00@gmail.com>                     <dons@galois.com>
 Duncan Coutts               <duncan@community.haskell.org>
 Duncan Coutts               <duncan@community.haskell.org>         <Duncan Coutts duncan@community.haskell.org>
 Duncan Coutts               <duncan@community.haskell.org>         <duncan.coutts@worc.ox.ac.uk>

AUTHORS

@@ -74,7 +74,7 @@ Dennis Gosnell           <cdep.illabout@gmail.com>
 Dino Morelli             <dino@ui3.info>
 Dmitry Astapov           <dastapov@gmail.com>
 Dominic Steinitz         <dominic@steinitz.org>
-Don Stewart              <dons@galois.com>
+Don Stewart              <dons00@gmail.com>
 Doug Beardsley           <mightybyte@gmail.com>
 Duncan Coutts            <duncan@community.haskell.org>
 Echo Nolan               <echo@echonolan.net>