Migrate remove group modal to vue

What does this MR do and why?

This MR migrates the confirmation modal used for removing groups from a HAML implementation to vue, this is related to the modal migration in #342116 (closed)

A slight visual change is introduced, the confirmation warning message is now wrapped in a GlAlert to better highlight the importantance of this information. This visual change to the modal is instroduced in !72663 (merged)

Screenshots or screen recordings

Before	After - scheduled deletion	After - permanent deletion

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

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 #345128 (closed)