Correct duo extension urls on get started page

What does this MR do and why?

Correct duo extension urls on get started page

fixes #532965 (closed)

References

Screenshots or screen recordings

No visual changes

How to set up and validate locally

1. Setup gdk to simulate SaaS - https://docs.gitlab.com/ee/development/ee_features.html#simulate-a-saas-instance and restart GDK

2. In rails console enable the feature flag

   Feature.enable(:learn_gitlab_redesign)

3. Create a new group and project.

4. In rails console, onboard that group that was just created

   ::Onboarding::Progress.onboard(Group.last)

5. In the gitlab admin UI, edit the group to be on an ultimate trial plan(edit button from http://gdk.test:3000/admin/groups)

6. In rails console(bundle exec rails c), change the trial, trial start and end date for the group

   Group.last.gitlab_subscription.update_columns(trial_starts_on: Date.today, trial_ends_on: 30.days.from_now, trial: true)

7. Go to the get started path for the group/project: For instance, http://gdk.test:3000/logan225-group/logan225-project/-/get_started

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #542982 (closed)