fixed spec - at last!

spec/services/system_note_service_spec.rb

@@ -428,15 +428,14 @@ describe SystemNoteService, services: true do
     context 'commit from fork' do
       let(:author2) { create(:user) }
       let(:forked_project) { Projects::ForkService.new(project, author2).execute }
-      let(:service) { CreateCommitBuildsService.new }
       let(:commit2) { forked_project.commit }
 
       before do
-        described_class.cross_reference(commit0, commit2, author2)
+        described_class.cross_reference(noteable, commit2, author2)
       end
 
       it 'is falsey when is a fork mentioning an external issue' do
-        expect(described_class.cross_reference_exists?(commit0, commit2)).
+        expect(described_class.cross_reference_exists?(noteable, commit2)).
             to be_falsey
       end
     end