message: utxo withdraw - fix default hashname
diff: @@ -794,7 +794,7 @@ class UTXOBlockchain extends SwapInterface {
  * @param {string} hashName
  * @returns {Promise}
  */
  - withdraw(data, isRefund?: boolean = false, hashName?: string = null): Promise<string> {
  + withdraw(data, isRefund?: boolean = false, hashName?: string): Promise<string> {
  return new Promise(async (resolve, reject) => {
  try {
  console.log('withdraw')
  @@ -873,7 +873,7 @@ class UTXOBlockchain extends SwapInterface {
  * @param {string} hashName
  * @returns {Promise}
  */
  - refund(data: any, hashName?: string = null) {
  + refund(data: any, hashName?: string) {
  return this.withdraw(data, true, hashName)
  }
  