[traveling-fastlane] Update app_produce to return App ID

[barthap]

By default, fastlane produce returns newly created App "Apple ID" number, which is then required for Transporter.app/fastlane pilot to upload binary to TestFlight without 2FA login.

This PR modifies app_produce.rb script to return then number to the caller as JSON result.

Example (using built package):

/dev/test_proj/node_modules/@expo/traveling-fastlane-darwin/dist/app_produce my.BundleName "Some ApName" my-apple-id@icloud.com English

Result:

...
[11:27:10]: Creating new app 'Some ApName' on App Store Connect
[11:27:18]: Waiting for the newly created application to be available on App Store Connect...
[11:27:34]: Ensuring version number
[11:27:34]: Successfully created new app 'Some ApName' on App Store Connect with ID 1538xxxxxx
{"result":"success","appleId":"1538xxxxxx"}