Fix attribution artist image not being set when loaded.
Fix attribution artist image not being set when loaded.

imojiengineering/imoji-ios-sdk-ui,imojiengineering/imoji-ios-sdk-ui,alex-hoang/imoji-ios-sdk-ui,alex-hoang/imoji-ios-sdk-ui,imojiengineering/imoji-ios-sdk-ui,alex-hoang/imoji-ios-sdk-ui,alex-hoang/imoji-ios-sdk-ui,imojiengineering/imoji-ios-sdk-ui