test(Dropdown): add common
test(Dropdown): add common

Semantic-Org/Semantic-UI-React,jcarbo/stardust,Rohanhacker/Semantic-UI-React,clemensw/stardust,ben174/Semantic-UI-React,koenvg/Semantic-UI-React,aabustamante/Semantic-UI-React,vageeshb/Semantic-UI-React,aabustamante/Semantic-UI-React,Semantic-Org/Semantic-UI-React,mohammed88/Semantic-UI-React,aabustamante/Semantic-UI-React,jamiehill/stardust,clemensw/stardust,koenvg/Semantic-UI-React,Rohanhacker/Semantic-UI-React,vageeshb/Semantic-UI-React,mohammed88/Semantic-UI-React,ben174/Semantic-UI-React