fix: If starting a new chat, citation panel should get closed automatically

Merge pull request #383 from microsoft/psl-bug-17493

Author: Avijit-Microsoft

src/App/src/components/Chat/Chat.tsx

@@ -718,6 +718,7 @@ const Chat: React.FC<ChatProps> = ({
 
   const onNewConversation = () => {
     dispatch({ type: actionConstants.NEW_CONVERSATION_START });
+    dispatch({  type: actionConstants.UPDATE_CITATION,payload: { activeCitation: null, showCitation: false }})
   };
   const { messages, citations } = state.chat;
   return (