Upgrade SDK to 1.20.0 (#170)

Author: danield9tqh

package-lock.json

@@ -22,7 +22,7 @@
   },
   "license": "MPL-2.0",
   "dependencies": {
-    "@ironfish/sdk": "1.19.0",
+    "@ironfish/sdk": "1.20.0",
     "electron-serve": "^1.1.0"
   },
   "devDependencies": {

package.json

@@ -24,18 +24,18 @@ import { ViewOnlyChip } from "../ViewOnlyChip/ViewOnlyChip";
 type FormatTypes = `${AccountFormat}`;
 
 const viewOnlyFormatOptions: Map<string, FormatTypes> = new Map([
-  ["Bech32", "Bech32"],
+  ["Base64Json", "Base64Json"],
   ["JSON", "JSON"],
 ]);
 
 const formatOptions: Map<string, FormatTypes> = new Map([
-  ["Bech32", "Bech32"],
+  ["Base64Json", "Base64Json"],
   ["JSON", "JSON"],
   ["Mnemonic", "Mnemonic"],
   ["Spending Key", "SpendingKey"],
 ]);
 
-const defaultFormat: FormatTypes = "Bech32";
+const defaultFormat: FormatTypes = "Base64Json";
 
 const messages = defineMessages({
   exportAccount: {