maintainers: add _414owen

maintainers/maintainer-list.nix

···
     githubId = 882455;
     name = "Elliot Cameron";
   };
+  _414owen = {
+    email = "[e-mail]";
+    github = "414owen";
+    githubId = 1714287;
+    name = "Owen Shepherd";
+  };
   _6AA4FD = {
     email = "[e-mail]";
     github = "6AA4FD";