Open TODOs in TransactionBuilder.ts

[mr-zwets]

There's 3 open TODOs in TransactionBuilder.ts which have been there since more than a year (13 months atm)

  // TODO: allow uint8array for chunks
  addOpReturnOutput(chunks: string[]): this {
  ...

// TODO: see if we can merge with Transaction.ts
  async send(): Promise<TransactionDetails>;

  // TODO: see if we can merge with Transaction.ts
  private async getTxDetails(txid: string): Promise<TransactionDetails>;