fix: add correct script on Android (#596)

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### Summary

Fixes a regression where `build-android` contained a script for building
iOS app.

### Test plan

`build:android` should contain script for building Android app.

Author: szymonrybczak

packages/create-react-native-library/src/utils/generateExampleApp.ts

@@ -163,7 +163,7 @@ export default async function generateExampleApp({
     const iosBuild = [
       'npm run mkdist',
       'react-native bundle --entry-file index.js --platform ios --dev true --bundle-output dist/main.ios.jsbundle --assets-dest dist',
-      SCRIPTS_TO_ADD['build:android'],
+      SCRIPTS_TO_ADD['build:ios'],
     ].join(' && ');
 
     Object.assign(scripts, {