Gate trial CTA's on FF automatic_self_managed_trial_activation

What does this MR do and why?

Gate trial CTA's on FF automatic_self_managed_trial_activation

Changelog: changed EE: true

https://gitlab.com/gitlab-org/customers-gitlab-com/-/work_items/16943

References

Screenshots or screen recordings

n/a

How to set up and validate locally

1. Restart GDK in self managed
   1. export GITLAB_SIMULATE_SAAS=0
2. Enable the Feature flag
   1. Go to http://127.0.0.1:3000/rails/features/
   2. Search and enable automatic_self_managed_trial_activation
3. Log in as administrator
4. Go to: [http://127.0.0.1:3000/dashboard/projects]
5. Check that trial link points to internal form

MR acceptance checklist

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