meshcentral: use fetchYarnDeps

pkgs/tools/admin/meshcentral/default.nix

@@ -1,4 +1,10 @@
-{ lib, fetchzip, yarn2nix-moretea, nodejs_18, dos2unix }:
+{ lib
+, fetchzip
+, fetchYarnDeps
+, yarn2nix-moretea
+, nodejs_18
+, dos2unix
+}:
 
 yarn2nix-moretea.mkYarnPackage {
   version = "1.1.6";
@@ -12,7 +18,11 @@ yarn2nix-moretea.mkYarnPackage {
 
   packageJSON = ./package.json;
   yarnLock = ./yarn.lock;
-  yarnNix = ./yarn.nix;
+
+  offlineCache = fetchYarnDeps {
+    yarnLock = ./yarn.lock;
+    hash = "sha256-aKWa6pvIi2JkOtpiWH19KZoncPuSIgvDk/j7PvXp2nw=";
+  };
 
   # Tarball has CRLF line endings. This makes patching difficult, so let's convert them.
   nativeBuildInputs = [ dos2unix ];