Step-by-step identity verification

Partially resolves: https://gitlab.com/gitlab-org/modelops/anti-abuse/team-tasks/-/issues/83

What does this MR do and why?

Update the identity verification feature to have new users go through multiple identity verification steps one at a time.

Before this MR, only code email verification was required if identity_verification feature flag is enabled. With this MR, users must go through credit card verification (behind identity_verification_credit_card feature flag) and then email verification in order.

Note: identity_verification_credit_card requires identity_verification to be enabled.

Screenshots or screen recordings

https://www.loom.com/share/c21b2d212e6a4eb19bedd063978e948c

How to set up and validate locally

1. Ensure that you have a running CustomersDot installation locally and Zuora is set up to use GL.com CC Validation_registration hosted page with the correct callback to your local GDK instance
2. Enable relevant feature flags

   $ rails console
   > Feature.enable(:identity_verification)
   > Feature.enable(:identity_verification_credit_card)

3. Sign up for a new account. After, you should be redirected to the Identity Verification page (http://localhost:3000/users/identity_verification)
4. Validate that the credit card verification step is shown on the Identity Verification page
   📸

   
5. Fill up and submit the form with the following values

   Name on card: Any name
   Card number: 4242 4242 4242 4242
   Expiration date: Any future date
   CVC: Any 3-digit number

6. Validate that the credit card verification step card collapses and shows a check icon after successful verification
   📸

   
7. Validate that the email verification step expands

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.