ocamlPackages.iter: use Dune 2

pkgs/development/ocaml-modules/iter/default.nix

@@ -1,9 +1,13 @@
-{ lib, fetchFromGitHub, buildDunePackage, ocaml, mdx, qtest, result }:
+{ lib, fetchFromGitHub, buildDunePackage, ocaml, dune-configurator
+, mdx, qtest, result
+}:
 
 buildDunePackage rec {
   pname = "iter";
   version = "1.2.1";
 
+  useDune2 = true;
+
   src = fetchFromGitHub {
     owner = "c-cube";
     repo = pname;
@@ -11,10 +15,11 @@ buildDunePackage rec {
     sha256 = "0j2sg50byn0ppmf6l36ksip7zx1d3gv7sc4hbbxs2rmx39jr7vxh";
   };
 
-  buildInputs = lib.optionals doCheck [ mdx.bin qtest ];
+  buildInputs = [ dune-configurator ];
   propagatedBuildInputs = [ result ];
 
   doCheck = lib.versionAtLeast ocaml.version "4.07";
+  checkInputs = [ mdx.bin qtest ];
 
   meta = {
     homepage = "https://github.com/c-cube/sequence";