Account validation email event tracking

What does this MR do and why?

⚠ This functionality is EE-only ⚠

This MR is part of #346233 (closed).

It adds Snowplow event tracking for the following actions:

1. When the user clicks on the CTA button of Account Validation email. The tracking happens in /:group_id/:project_id/-/pipelines/:pipeline_id/validate_account endpoint where the user is redirected after clicking on the email CTA button

   Account validation email CTA button

   

2. When the user successfully validates their account from the pipeline page.

   Account validation modal in pipeline page

   

Screenshots or screen recordings

The following recordings show the events as they show in Snowplow Micro.

When user clicks on Account Validation email CTA button

https://youtu.be/oaOPzU20xJ4

When user successfully validates their account in pipeline page

Note: In the video, I set up the code to behave like the validation succeeded right after clicking on the Validate account button in the modal

https://youtu.be/oycp4pFMQxQ

How to set up and validate locally

When the user clicks on the CTA button of Account Validation email

1. Have a pipeline that failed with the user_not_verified failure reason
2. Have a working Snowplow Micro setup
3. Send the Account Validation email using the failed pipeline
4. Click on the CTA button in the email
5. Verify that you are redirected to the pipeline page
6. Verify that a Snowplow event was emitted in Snowplow Micro

Setting this all up requires a lot of time so here's a video where I validate this locally:

https://youtu.be/oaOPzU20xJ4

When the user successfully validates their account from the pipeline page.

1. The CustomersDot application needs to be setup locally
2. A Zuora payment page needs to be created on the Zuora API Sandbox with the local GDK URL configured
3. The Zuora payment page ID needs to be configured in CustomersDot
4. A pipeline needs to be created by a user with the user_not_verified failure reason

Local setup for this one requires a lot of time too. To help with the review, here's a video where I validate this locally:

Note: In the video, I set up the code to behave like the validation succeeded right after clicking on the Validate account button in the modal

https://youtu.be/oycp4pFMQxQ

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.