client/core: do not disconnect on config timeout

If the config request started by refreshServerConfig on reconnect times
out, it should not disconnect the current connection.  The wsConn's
reconnect / keepAlive loop will deal with it.

client/core/bookie.go

@@ -591,7 +591,6 @@ func (dc *dexConnection) refreshServerConfig() error {
 	cfg := new(msgjson.ConfigResult)
 	err := sendRequest(dc.WsConn, msgjson.ConfigRoute, nil, cfg, DefaultResponseTimeout)
 	if err != nil {
-		dc.connMaster.Disconnect()
 		return fmt.Errorf("unable to fetch server config: %w", err)
 	}