maintainers: add email for jappie3 (#407892)

Author: Sigmanificient

maintainers/maintainer-list.nix

@@ -11132,6 +11132,7 @@
     name = "Jappie Klooster";
   };
   jappie3 = {
+    email = "[email protected]";
     name = "Jappie3";
     matrix = "@jappie:jappie.dev";
     github = "Jappie3";