feat(app_check, mobile): add option to pass debugTokens in initialization

[xVemu]

Description

This feature allows a developer to use a pre-generated debug token instead of one that is generated at runtime. It's useful in CI environments, where you don't have an option to copy token from logs and paste it to Firebase Console.

Related Issues

Fix for: #11719

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
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Breaking Change

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• Yes, this is a breaking change.
• No, this is not a breaking change.

[Lyokone]

Hello @xVemu, thanks for your PR, could you add some tests in the tests/integration_test/firebase_app_check

[xVemu]

@Lyokone something like this?

[Lyokone]

Thanks, I'll have a look at the API (we might want to have appleDebugToken instead of iosDebugToken). But otherwise it looks good :)

[Fudal]

@xVemu any update for that?

[xVemu]

@xVemu any update for that?

I guess we have to wait for Firebase team?

[adonisRodxander]

@xVemu did you notice that some tests are failing?

[xVemu]

@xVemu did you notice that some tests are failing?

Yep, I assume that's because I haven't changed pubspec for related packages.

[MoaidAlrazhy]

@xVemu have you got anytime to fix this ?

[xVemu]

@xVemu have you got anytime to fix this ?

Fix what?

[MoaidAlrazhy]

@xVemu have you got anytime to fix this ?

Fix what?

the failing checks below that are blocking the PR.

[Fudal]

@xVemu are you able to tell who should doing something to merge it?