Adding Integration Test for Phone Number Authentication in Firebase

[srushtisv]

Implement integration test for verifying phone number sign-in with Firebase Auth. Please review and approve.

[google-oss-bot]

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[paulb777]

LLC is missing. See other files in the repo or https://github.com/firebase/firebase-ios-sdk/blob/main/scripts/check_copyright.sh#L21

[ncooke3]

Thanks for working on tests. The new file should be added to the SwiftApiTests target in the Xcode project so it builds and runs.

When I do that locally, it has some failures.

Also, it would be great to test the async variations of the APIs as well.

confirmed they are building and running:

PhoneAuthTests
    ✓ testSignInWithPhoneNumber (0.997 seconds)
    ✓ testSignInWithPhoneNumberAsync_Success (1.066 seconds)

from https://github.com/firebase/firebase-ios-sdk/actions/runs/10625088625/job/29454486166?pr=13538#step:6:340

[srushtisv]

Thanks for working on tests. The new file should be added to the SwiftApiTests target in the Xcode project so it builds and runs.

When I do that locally, it has some failures.

Also, it would be great to test the async variations of the APIs as well.

done

[paulb777]

@srushtisv Any reason this code hasn't yet merged to main? Ideally, we should merge larger PRs to main as soon as possible to avoid unnecessary branching.