fix: historical chats appear in the new user's chat box #256 (#282)

### What problem does this PR solve?

historical chats appear in the new user's chat box

Issue link:#256

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

web/src/pages/chat/model.ts

@@ -97,6 +97,7 @@ const model: DvaModel<ChatModelState> = {
       if (data.retcode === 0) {
         yield put({ type: 'setDialogList', payload: data.data });
       }
+      return data;
     },
     *listConversation({ payload }, { call, put }) {
       const { data } = yield call(chatService.listConversation, payload);