Set Learn GitLab > CI/CD to link to /-/pipelines page

What does this MR do and why?

Change link as described in #390257 (closed)

Screenshots or screen recordings

local development pipelines page(confirmed will look like this in production - #388970 (comment 1253965635)):

How to set up and validate locally

note basically trying to emulate feature spec steps in ee/spec/features/registrations/saas/standard_flow_just_me_creating_project_spec.rb

1. Setup to simulate SaaS and restart GDK
   • Make sure Admin > Settings > General > Sign Up Restrictions match the below (no admin approval, but hard email confirmation)
2. Register as a new user.
3. Confirm email by finding the confirmation path from last User created in rails console
   • Rails.application.routes.url_helpers.user_confirmation_path(confirmation_token: User.last.confirmation_token)
4. Visit the path from the previous step.
5. You should be on the sign in page, log back in.
6. Select any 'role' and 'Just me' in the welcome form after sign up step.
7. Choose 'Create a new project'
8. Click 'Continue'
9. Fill out fields to create a group and project on the next page.
10. Click 'Create project'
11. Verify you get to the onboarding and page refreshes to provide a "Ok, let's go" button.
12. Click on "Ok, let's go" and verify you are dropped into the learn gitlab project and the celebrate modal pops up with confetti
13. Close the invite modal and click on the Set up your first project's CI/CD link in the Set up your workspace card.

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.

Related to #390257 (closed)