make Display Tandem.OPTIONAL and don't hard code tandems for UtteranceQueue, https://github.com/phetsims/scenery/issues/1183
make Display Tandem.OPTIONAL and don't hard code tandems for UtteranceQueue, https://github.com/phetsims/scenery/issues/1183

phetsims/joist,phetsims/joist,phetsims/joist