maintainer-list.nix: add kilianar

maintainers/maintainer-list.nix

···
     githubId = 845652;
     name = "Kier Davis";
   };
+  kilianar = {
+    email = "[e-mail]";
+    github = "kilianar";
+    githubId = 105428155;
+    name = "kilianar";
+  };
   kilimnik = {
     email = "[e-mail]";
     github = "kilimnik";