maintainers: add encode42

maintainers/maintainer-list.nix

···
     githubId = 28287;
     name = "Jon Roberts";
   };
+  encode42 = {
+    name = "encode42";
+    email = "[e-mail]";
+    github = "encode42";
+    githubId = 34699884;
+  };
   enderger = {
     email = "[e-mail]";
     github = "enderger";