[PM-8051] Fix WebAuthenticator getting the Window properly on iOS Autofill extension 2FA WebAuthn

[fedemkr]

Type of change

• [X] Bug fix
• [ ] New feature development
• [ ] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
• [ ] Build/deploy pipeline (DevOps)
• [ ] Other

Objective

Fix for WebAuthn 2FA not working on iOS Autofill extension given that the UIWindow was not getting properly gotten. This fixes it by using our custom workaround for it. This affects WebAuthn as well as could affect Captcha views.

Code changes

• All: Applied workaround to use ShouldUseSharedApplicationKeyWindow when coming from iOS extension and updated callers to properly pass FromIosExtension flag to it gets applied correctly.

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