Create the standalone vulnerability page

In order to start working on the standalone vulnerabilities, we need a page to render them. This is not the full MVC outlined in #13561 (closed), but the first step towards it.

This will need to be:

• Be accessible via a unique url e.g. https://gitlab.com/gitlab-org/gitlab/security/dashboard/12345
• Display the appropriate data in the description (see screenshots)
• Display the appropriate title in both the description an in the page <title>
• Display the appropriate breadcrumbs
• Be hidden behind the first_class_vulnerabilities feature flag

If we can do it at this stage, we should also include:

• The current vulnerability status
• [-] The pipeline information where the vulnerability was discovered

Designs

URLs

Page	URL	Feature flag	Notes
Project Security dashboard	gitlab.com/[group]/[project]/security/dashboard	❌	No change to current behavior
Standalone Vulnerability page	gitlab.com/[group]/[project]/security/dashboard/[vuln_id]	first_class_vulnerabilities
Vulnerability list	gitlab.com/[group]/[project]/security/dashboard/list	first_class_vulnerabilities	This page is temporary and will list the vulnerabilties. It needs to be removed once the first class vulnerabilties feature flag has been removed