message: fix(utxo-lib): remove unnecessary asyncs
  Issue:
diff: @@ -127,12 +127,12 @@ describe('WalletUnspent', function () {
  });
  });
  - async function constructAndSignTransactionUsingPsbt(
  + function constructAndSignTransactionUsingPsbt(
  unspents: WalletUnspent<bigint>[],
  signer: string,
  cosigner: string,
  scriptType: outputScripts.ScriptType2Of3
  - ): Promise<Transaction<bigint>> {
  + ): Transaction<bigint> {
  const psbt = createPsbtForNetwork({ network });
  const total = BigInt(unspentSum<bigint>(unspents, 'bigint'));
  // Kinda weird, treating entire value as change, but tests the relevant paths
  @@ -210,7 +210,7 @@ describe('WalletUnspent', function () {
  amountType: 'number' | 'bigint' = 'number',
  testOutputAmount = toTNumber<TNumber>(defaultTestOutputAmount, amountType)
  ) {
  - it(`can be signed [scriptType=${scriptType} signer=${signer} cosigner=${cosigner} amountType=${amountType}]`, async function () {
  + it(`can be signed [scriptType=${scriptType} signer=${signer} cosigner=${cosigner} amountType=${amountType}]`, function () {
  const unspents = [
  mockWalletUnspent(network, testOutputAmount, {
  keys: walletKeys,
  @@ -231,7 +231,7 @@ describe('WalletUnspent', function () {
  scriptType
  );
  if (amountType === 'bigint') {
  - const psbtTransaction = await constructAndSignTransactionUsingPsbt(
  + const psbtTransaction = constructAndSignTransactionUsingPsbt(
  unspents as WalletUnspent<bigint>[],
  signer,
  cosigner,
  