rpcwallet: Add TransactionBuilder argument to AsyncRPCOperation_sendmany

src/transaction_builder.h

@@ -69,6 +69,7 @@ private:
     boost::optional<CTxDestination> tChangeAddr;
 
 public:
+    TransactionBuilder() {}
     TransactionBuilder(const Consensus::Params& consensusParams, int nHeight, CKeyStore* keyStore = nullptr);
 
     void SetFee(CAmount fee);