Fix ProcessReferencesWorker error for tasks before update

spec/workers/process_references_worker_spec.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe ProcessReferencesWorker do
+  let(:worker) { described_class.new }
+
+  describe 'perform' do
+    it 'runs without error for simple call' do
+      expect { worker.perform(1000, [], []) }.to_not raise_error
+    end
+
+    it 'runs without error with no_fetch_urls' do
+      expect { worker.perform(1000, [], [], no_fetch_urls: []) }.to_not raise_error
+    end
+  end
+end