Add report for Sec Section recently closed issues

The intent of this report is to replace the manual runs of https://gitlab.com/gitlab-org/secure/tools/report-scripts.

It's scheduled to run every Monday at 3am.

Example output: triage-reports#5018 (closed)

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 =>
  • Week-in-review