Change remediated badge icon from wrench to check-circle-dashed

What does this MR do and why?

On the vulnerability report, if a vulnerability is no longer detected, a wrench icon is shown on the right. This icon should only be used for linking to the admin section only. This MR replaces it with check-circle-dashed instead.

Before	After

How to set up and validate locally

It's pretty involved to get the badge to show and this is just an icon change, so I negated the v-if on this line to get the badge to show:

https://gitlab.com/gitlab-org/gitlab/blob/master/ee/app/assets/javascripts/security_dashboard/components/shared/vulnerability_list.vue#L432-432

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 #334917 (closed)