Instructions:

1- Create an apple developer account
2- Setup App and Service ID's
3- Ensure that redirect url in the service id is valid and is for
    both test and live versions
4- Add you Redirect Url and Secret key in your plugin
    section
5- Test the Integration

Note:

1- Make sure that your button has this id "custom-apple-
   signin-button"
2- Once the id is attached to any button on the page, it will
    trigger the apple form
3- Ensure that the URL where your element is hosted
    matches the redirect URI specified in your Apple Service
    ID. Both should be the same for proper authentication

State:

1- Email
2- Sub (User's unique id in apple database)

Event:

1- When the user successfully gets authenticated to our
        app with a email and a sub.