iOS Push Notifications guide outdated and incomplete

[kevinfoley]

The documentation for setting up push notifications on iOS has several issues:

1. The example code uses a deprecated Unity API, UnityEngine.iOS.NotificationServices.RegisterForNotifications(). New projects should use the Mobile Notifications package
2. The tutorial cannot be followed in a cross-platform application that implements Push Notifications on Android. The PlayFab documentation for Android push notifications directs us to use Firebase Cloud Messaging (FCM). If the FCM plugin is installed, on iOS it hijacks the normal notification APIs via swizzling. When we attempt to request user authorization to display notifications, we get an error "Attempting to complete future before FCM initialized."

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Document Details

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• ID: 456f36b2-0825-fe0e-9681-29b95bb6d050
• Version Independent ID: 8c38a5f4-b4f1-4d4c-bc4e-467d369c3fca
• Content: Push Notification for iOS - PlayFab
• Content Source: playfab-docs/features/engagement/push-notifications/push-notifications-for-ios.md
• Service: playfab
• GitHub Login: @joannaleecy
• Microsoft Alias: joanlee