Update ConcurrentPipelinesVerificationAlert Vue component

What does this MR do and why?

https://gitlab.com/groups/gitlab-org/modelops/anti-abuse/-/epics/32 requirements changed from disallowing users to run concurrent pipelines to disallowing users to run pipelines entirely if they haven't completed identity verification.

This MR updates the alert component that will be shown to users to remove "concurrent" from the title and change the variant from "warning" to "danger".

MR acceptance checklist

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

Screenshots or screen recordings

Before	After