remove unused line in sort.js
remove unused line in sort.js

uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,uwdata/vega-lite,vega/vega-lite,uwdata/vega-lite,vega/vega-lite,vega/vega-lite,vega/vega-lite,ellisonbg/vega-lite,ellisonbg/vega-lite,vega/vega-lite,ellisonbg/vega-lite