FE: Detailed Visibility -- Overhaul copy for container registry warning

What does this MR do and why?

Resolves: https://gitlab.com/gitlab-org/gitlab/-/issues/418787

This MR updates the copy in the warning popover to better reflect which actions are required from the user.

Screenshots or screen recordings

NA

How to set up and validate locally

Open a namespace's Usage Quotas, Storage tab (e.g. http://localhost:3000/groups/gitlab-instance-3d22f6d0/-/usage_quotas#storage-quota-tab)

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 #418787