fix: default values

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gas-price-oracle",
-  "version": "0.4.2",
+  "version": "0.4.3",
   "description": "Gas Price Oracle library for Ethereum dApps.",
   "main": "lib/index.js",
   "homepage": "https://github.com/peppersec/gas-price-oracle",

src/index.ts

@@ -17,8 +17,8 @@ import {
 const defaultFastGas = 22;
 export class GasPriceOracle {
   lastGasPrice: GasPrice;
-  offChainOracles: OffChainOracles;
-  onChainOracles: OnChainOracles;
+  offChainOracles: OffChainOracles = {};
+  onChainOracles: OnChainOracles = {};
   configuration: Config = {
     chainId: ChainId.MAINNET,
     defaultRpc: 'https://api.mycryptoapi.com/eth',