Add count_distinct_projects_with_resolved_REPORT_TYPE_vulnerabilities metric definitions

Proposal

In support of &12499 (closed) we need to add an additional metric definition for percentage of security scans with resolved vulnerabilities.

The initial work was done with Add count_of_distinct_report_types_with_resolve... (#461890 - closed) but to get more granular data a request was made to include distinct counts of projects per report type (called "scanner" in linked issue)

• backend Create metric definitions for each report type
• backend include metric in Service ping