message: Fix HelloCocoaPods iOS sample
diff: @@ -153,7 +153,7 @@ struct Vertex {
  // Compile for Metal on mobile platforms.
  .targetApi(filamat::MaterialBuilder::TargetApi::METAL)
  .platform(filamat::MaterialBuilder::Platform::MOBILE)
  - .build();
  + .build(_engine->getJobSystem());
  assert(pkg.isValid());
  // We're done building materials.
  