Fix Mentionable spec

spec/models/concerns/mentionable_spec.rb

@@ -8,7 +8,7 @@ describe Mentionable do
 
     it 'excludes JIRA references' do
       allow(project).to receive_messages(jira_tracker?: true)
-      expect(references(project, 'JIRA-123')).to be_empty
+      expect(referenced_mentionables(project, 'JIRA-123')).to be_empty
     end
   end
 end