fix query conn

proxy/app_conn.go

@@ -127,6 +127,10 @@ func (app *appConnQuery) Error() error {
 	return app.appConn.Error()
 }
 
+func (app *appConnQuery) EchoSync(msg string) (res types.Result) {
+	return app.appConn.EchoSync(msg)
+}
+
 func (app *appConnQuery) InfoSync() (res types.Result) {
 	return app.appConn.InfoSync()
 }

proxy/multi_app_conn.go

@@ -114,7 +114,7 @@ func (app *multiAppConn) OnStart() error {
 	if err != nil {
 		return err
 	}
-	app.queryConn = NewAppConnMempool(querycli)
+	app.queryConn = NewAppConnQuery(querycli)
 
 	// mempool connection
 	memcli, err := NewTMSPClient(addr, transport)