[ci] Upgrades yojson.

nix/yojson.nix

-{ lib, fetchurl, buildDunePackage, cppo, easy-format, biniou }:
+{ lib, fetchurl, buildDunePackage, cppo, seq }:
 
 buildDunePackage rec {
   pname = "yojson";
-  version = "1.7.0";
+  version = "2.0.2";
   useDune2 = true;
 
   src = fetchurl {
     url = "https://github.com/ocaml-community/yojson/releases/download/${version}/yojson-${version}.tbz";
-    sha256 = "1iich6323npvvs8r50lkr4pxxqm9mf6w67cnid7jg1j1g5gwcvv5";
+    sha256 = "sha256-h2u284r3OoSilDij2jXkhXxgoUVWpgZSWxSMb9vlRhs=";
   };
 
   nativeBuildInputs = [ cppo ];
-  propagatedBuildInputs = [ easy-format biniou ];
+  propagatedBuildInputs = [ seq ];
 
   meta = with lib; {
     description = "An optimized parsing and printing library for the JSON format";