[iOS] Universal link not working as redirect URI

## Issue

Hi,

I am facing the problem that my https redirect URI is not working when using the normal authentication through the browser popup window. However, if I set the customBrowser to Safari, it works. This will open up the Safari browser in a external window. After swichting back to the popup window it works, but only for a limited time. After some time the Universal links stop working (Properly because the associated domains are cached somehow?). I have the feeling the apple app site association file is not loaded correctly, when the external browser is not opened once.

The use of the external (or default web browser) variant is not accepted by Apple App Review anymore, because of bad user experience.

If anyone could solve this problem, please contact me!

Thanks!
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## Environment
Keycloak
* **Platform that you're experiencing the issue on**: `iOS`
* **Your `react-native` Version**: `e.g. 0.72.1`
* **Your `react-native-app-auth` Version**: `e.g. 7.0.0`
* **Are you using Expo?**
no

まず、iOS の react-native-app-auth で Keycloak の HTTPS リダイレクトフローを再現し、通常のブラウザポップアップと Safari を比較して、issue に記載されている Universal Links と Apple App Site Association の動作を確認します。ポップアップから redirect URI が外部ブラウザを必要とせず安定して動作すれば完了です。このレポートではファイルもテストも指定しません。

索引モデルが issue の本文から書いたものです。