message: remove extra byte at the end of the preorder
diff: @@ -148,7 +148,7 @@ export function makePreorderSkeleton(
  const hashed = hash160(dataBuff)
  - const opReturnBufferLen = burnAmount.units === 'BTC' ? 40 : 48
  + const opReturnBufferLen = burnAmount.units === 'BTC' ? 39 : 66
  const opReturnBuffer = Buffer.alloc(opReturnBufferLen)
  opReturnBuffer.write('id?', 0, 3, 'ascii')
  hashed.copy(opReturnBuffer, 3)
  @@ -158,8 +158,8 @@ export function makePreorderSkeleton(
  const burnHex = burnAmount.amount.toHex()
  const paddedBurnHex = `0000000000000000${burnHex}`.slice(-16)
  - opReturnBuffer.write(paddedBurnHex, 40, 8, 'hex')
  - opReturnBuffer.write(burnAmount.units, 48, burnAmount.units.length, 'ascii')
  + opReturnBuffer.write(paddedBurnHex, 39, 8, 'hex')
  + opReturnBuffer.write(burnAmount.units, 47, burnAmount.units.length, 'ascii')
  }
  const nullOutput = bitcoin.script.nullDataOutput(opReturnBuffer)
  