Enhance Vulnerability Report for archived projects

Proposal

A GitLab customer contacted Support in this ticket to indicate an interest in improvements to the Vulnerability Report feature. Specifically, they'd like to see:

• Add the ability for the vulnerability report to optionally check archived projects within a group, including the last pipeline prior to being archived. This should be included in the UI as well as CSV output, if enabled.
• As security scans such as secret detection are 'read only', consider a way in which an archived project can be re-scanned on a periodic basis. This might be useful in situations where for compliance you must ensure that an archived project does not have newly identified secrets being found in archived projects.