update imports for React 18

Change-Id: Ibc75ce532003a478b31d5d85d84c83a017262041
diff --git a/client/src/components/ConversationList.js b/client/src/components/ConversationList.js
index 28ecbd5..d81ebb2 100644
--- a/client/src/components/ConversationList.js
+++ b/client/src/components/ConversationList.js
@@ -1,5 +1,5 @@
 import List from '@mui/material/List'
-import React, { useEffect } from "react";
+import { useEffect } from "react";
 import ConversationListItem from './ConversationListItem'
 import ListSubheader from '@mui/material/ListSubheader';
 import Conversation from '../../../model/Conversation';