Blinding: update change_position after calling fillBlindDetails

Author: psgreco

src/wallet/spend.cpp

@@ -1446,6 +1446,8 @@ static bool CreateTransactionInternal(
             return false;
         }
         txNew = tx_blinded; // sigh, `fillBlindDetails` may have modified txNew
+        // Update the change position to the new tx
+        change_position = txNew.vout.begin() + nChangePosInOut;
 
         int ret = BlindTransaction(blind_details->i_amount_blinds, blind_details->i_asset_blinds, blind_details->i_assets, blind_details->i_amounts, blind_details->o_amount_blinds, blind_details->o_asset_blinds, blind_details->o_pubkeys, issuance_asset_keys, issuance_token_keys, tx_blinded);
         assert(ret != -1);