feat(auth): add email MFA support

[PG-practice]

Problem

Add support for email-based MFA.

Issue number, if available:
#2159

Changes

• Add email MFA support

Corresponding docs PR, if applicable:
https://aws.amazon.com/about-aws/whats-new/2024/09/amazon-cognito-user-pools-email-authentication-option/
https://docs.amplify.aws/react/build-a-backend/auth/concepts/multi-factor-authentication/

Validation

• Added unit tests for happy path scenarios.
• Manually deploy with npx ampx sandbox command and check the userpool setting.

Checklist

• If this PR includes a functional change to the runtime behavior of the code, I have added or updated automated test coverage for this change.
• If this PR requires a change to the Project Architecture README, I have included that update in this PR.
• If this PR requires a docs update, I have linked to that docs PR above.
• If this PR modifies E2E tests, makes changes to resource provisioning, or makes SDK calls, I have run the PR checks with the run-e2e label set.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[changeset-bot]

🦋 Changeset detected

Latest commit: 9251415

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@aws-amplify/auth-construct	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR