fix(abstract-utxo): export transaction

TICKET: COIN-5426

Author: bhavidhingra

modules/abstract-utxo/src/index.ts

@@ -7,3 +7,4 @@ export * from './sign';
 export { UtxoWallet } from './wallet';
 export * as descriptor from './descriptor';
 export * as offlineVault from './offlineVault';
+export * as transaction from './transaction';