keychain: add sigma as maintainer

lib/maintainers.nix

@@ -477,6 +477,7 @@
   shell = "Shell Turner <cam.turn@gmail.com>";
   shlevy = "Shea Levy <shea@shealevy.com>";
   siddharthist = "Langston Barrett <langston.barrett@gmail.com>";
+  sigma = "Yann Hodique <yann.hodique@gmail.com>";
   simonvandel = "Simon Vandel Sillesen <simon.vandel@gmail.com>";
   sjagoe = "Simon Jagoe <simon@simonjagoe.com>";
   sjmackenzie = "Stewart Mackenzie <setori88@gmail.com>";

pkgs/tools/misc/keychain/default.nix

@@ -38,5 +38,6 @@ stdenv.mkDerivation rec {
     platforms =
       with stdenv.lib;
       platforms.linux ++ platforms.darwin;
+    maintainers = with stdenv.lib.maintainers; [ sigma ];
   };
 }