fix(android): bump Auth0.Android to 3.21.1 for Keystore2 INCOMPATIBL_DEVICE fix

[utkrishtsahu]

Changes

Bumps the bundled Auth0.Android dependency from `3.21.0` to `3.21.1` in `android/build.gradle`.

That release fixes credential storage failing with `INCOMPATIBLE_DEVICE` on newer Keystore2 hardware (Pixel 10, Galaxy S26, Android 16+). The RSA key used by `SecureCredentialsManager` was generated without explicitly authorizing MGF1 digests, which the newer firmware strictly enforces. Auth0.Android now authorizes both SHA-1 and SHA-256 and recreates a stale key on mismatch.

Nothing changes in this SDK's public API. This GA version replaces the `3.21.1-beta.0` pin from #1642, which only landed on the `v5.11.0-release` branch and not on `master`.

References

• https://github.com/auth0/Auth0.Android/releases/tag/3.21.1
• fix(storage): authorize MGF1 digest to prevent INCOMPATIBLE_DEVICE on…3.x Auth0.Android#1048
• fix(android): bump Auth0.Android to 3.21.1-beta.0 for Keystore2 INCOMPATIBLE_DEVICE fix #1642

Testing

• `yarn typecheck` clean, `yarn lint` 0 errors, `yarn test` 728 tests pass.

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• android/build.gradle

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📝 Summary

Summary by CodeRabbit

• Chores
  • This update includes no changes to app features or behavior visible to end users. No new capabilities, interface updates, or bug fixes are included in this release. The update is limited to internal maintenance, so there are no specific actions or changes for users to expect.

The Android build updates its Auth0 Android implementation dependency from version 3.21.0 to 3.21.1.

Changes: Android dependency update

Layer / File(s)	Summary
Update Auth0 Android dependency android/build.gradle	The declared Auth0 Android implementation dependency changes from version 3.21.0 to 3.21.1.

Priority: ➖ Normal

Estimated code review effort: 1 (Trivial) | ~4 minutes

Change: Bug fix

Suggested reviewers: subhankarmaiti

Merge Risk: ⚪ Minimal · up to ba480

The Android SDK patch update preserves the inspected MFA listing and enrollment behavior. No user-facing regression or actionable merge-blocking risk is established.

### Architecture Summary

Architecture risk: 🔵 Low · up to ba480

The change affects 1 system.

Changed systems: android

Architecture concerns
No architecture-level concerns identified.

Review details

Systems and components

• observed — android (service) was modified; 1 changed file maps to changed impact.

Before / after behavior

• observed — Modified behavior in android/build.gradle: The Auth0 Android implementation dependency is updated from version 3.21.0 to 3.21.1.

Pre-merge checks: 5

Passed checks: 5 passed

Check name	Status	Explanation
Title check		The title clearly identifies the Android dependency update to Auth0.Android 3.21.1 and the Keystore2 compatibility fix. It is specific and relevant despite a minor typo in "INCOMPATIBL_DEVICE."
Description check		The description directly explains the dependency update, the Keystore2 compatibility issue, the affected versions, references, and test results. It is relevant to the changeset.
Docstring Coverage		No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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