Enable vulnerabilitySeveritiesCount filtering by dismissal reason

The vulnerabilitySeveritiesCount does not currently provide capability to filter vulnerabilities by their dismissal reason. This is necessary to update the counts per severity when filtering on dismissal reason, done in Filter by dismissal reason on the Vulnerability... (#408983 - closed) • Samantha Ming • 16.3.

For queries:

1. Group.vulnerabilitySeveritiesCount
2. Project.vulnerabilitySeveritiesCount
3. InstanceSecurityDashboard.vulnerabilitySeverityCount

Implementation plan

1. Adjust ee/app/graphql/resolvers/vulnerability_severities_count_resolver.rb to allow filtering by dismissal reason