maintainers: add shellhazard

maintainers/maintainer-list.nix

···
     githubId = 251028;
     name = "Shell Turner";
   };
+  shellhazard = {
+    email = "[e-mail]";
+    github = "shellhazard";
+    githubId = 10951745;
+    name = "shellhazard";
+  };
   shelvacu = {
     name = "Shelvacu";
     email = "[e-mail]";