chore(sdk-coin-icp): export the required iface for icp

Ticket: WIN-4251

Author: adarsh312

modules/sdk-coin-icp/src/lib/index.ts

@@ -5,4 +5,5 @@ export { TransactionBuilder } from './transactionBuilder';
 export { TransferBuilder } from './transferBuilder';
 export { TransactionBuilderFactory } from './transactionBuilderFactory';
 export { Transaction } from './transaction';
+export { Signatures, SignatureType } from './iface';
 export { Utils };