Add processor to update pipeline status page

What does this MR do and why?

Step 1 for Notify failed master pipeline status in merge r... (#1497 - moved) • Jennifer Li • 16.11

Expected impact & dry-runs

I have tested the processor locally using my own token, and it was able to update the pipeline status page here.

The status page is currently hosted as a json file in the master-broken-incident project: https://gitlab.com/gitlab-org/quality/engineering-productivity/master-broken-incidents/-/blob/jennli-main-patch-1539/canonical-gitlab-master-pipeline-status.json

This can be easily moved to a different project/branch, and consider making it a gitlab page when necessary. Since pages need to be re-deployed through CI, a pipeline will need to be triggered by the processor somehow.

• As discussed with @splattael I think it's ok to not have this status page as a gitlab page for now.

Action items

• If adding environment variables for reactive processors, update config/triage-web.yaml and .gitlab/ci/triage-web.yml
• (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