Allow feedback form to be submitted without feedback text#5493

OEvgeny merged 14 commits intomicrosoft:mainmicrosoft/BotFramework-WebChat:mainfrom

lexi-taylor:users/lexitayor/feedbackform/no-message/buglexi-taylor/BotFramework-WebChat:users/lexitayor/feedbackform/no-message/bugCopy head branch name to clipboard