Remove faq link from storage limits alert

What does this MR do and why?

It removes the FAQ link from the storage limits alert, based on PM decision in https://gitlab.com/gitlab-org/gitlab/-/issues/432317#note_1722375813.

Note: no changelog since it is behind a feature flag.

Screenshots or screen recordings

Banner type	Before	After
Repository banner
Namespace banner

How to set up and validate locally

• Adjust ee/app/components/namespaces/storage/limit_alert_component.rb so the render? method returns true instead of the first line
• Navigate to a group
• Observe the banner showing without the FAQ link in its body

Related to #432317