Add CopySecurityIssueLabels processor

What does this MR do and why?

Adds a processor which copies all required labels from main repo issue to security implementation repo

Related: #902 (closed)

Expected impact & dry-runs

Action items

• (If applicable) Add documentation to the handbook pages for Triage Operations =>
• (If applicable) Identify the affected groups and how to communicate to them:
  • /cc @person_or_group =>
  • Relevant Slack channels =>
  • Engineering week-in-review

Closes #902 (closed)