Add CWEs and Severity level to ruleset

What does this MR do?

feat: Include CWEs and severities in report findings

• Includes mapping between eslint ruleIDs and CWEs
• Includes mapping between CWEs and normalized textual severities

See https://docs.google.com/spreadsheets/d/1SYKkODThUa80bWuCedTg9FLhyhvqLQ3tbZkMkjzq6vs/edit#gid=40027712 for mapping including CVSS and assorted notes

What are the relevant issue numbers?

Relates to gitlab-org&4004 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added
• [-] Documentation created/updated for GitLab EE, if necessary
• [-] Documentation created/updated for this project, if necessary
• [-] Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• [-] Job definition updated, if necessary
  • Auto-DevOps template
  • Job definition example
  • CI Templates
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer