Enhance add-on purchase flow for bookmarked/indexed URLs

Yes. If customers have bookmarked this URL or if they coming through the indexed URL from google then I wonder if https://gitlab.com/gitlab-org/customers-gitlab-com/-/merge_requests/12285 is the best solution to this since this will just redirect this customer to the subscriptions page. It will suppress the error but wont let these customers actually buy the add-on.

This ticket was created from INC-466 and was automatically exported by incident.io 🔥