isabelle-components.isabelle-linter: add platforms

pkgs/applications/science/logic/isabelle/components/isabelle-linter.nix

···
     homepage = "https://github.com/isabelle-prover/isabelle-linter";
     maintainers = with maintainers; [ jvanbruegge ];
     license = licenses.mit;
+    platforms = platforms.all;
   };
 }