fix(messaging, ios): register app delegate with google utilities for swizzling

[russellwheatley]

Description

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Related Issues

closes #13287
closes #13476
closes #12978

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Breaking Change

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[pamafe1976]

I confirm that this PR fixes #13287

[niosme]

Silent notifications works.
Also is not firing twice FirebaseMessaging.onMessage.listen for foreground notifications.
Background notifications works also FirebaseMessaging.onBackgroundMessage