Resolve "Create top 10 PI dashboard for centralized metric pages"

Why is this change being made?

Create top 10 metrics dashboard for centralized engineering pages: https://about.gitlab.com/handbook/engineering/metrics/#engineering-metrics-dashboards

Currently, there are 5 separate dashboards:

• Development: https://app.periscopedata.com/app/gitlab/681347/Development-Embedded-Dashboard
• Quality: https://app.periscopedata.com/app/gitlab/736012/Quality-Embedded-Dashboard
• Infrastructure: https://app.periscopedata.com/app/gitlab/798401/Infrastructure-Embedded-Dashboard
• UX: https://app.periscopedata.com/app/gitlab/736036/UX-Embedded-Dashboard
• Security: https://app.periscopedata.com/app/gitlab/758795/Appsec-Embedded-Dashboard

The goal is to pick the top 10 metrics, create a separate dashboard, and surface this at the top of the centralized handbook pages.

• Interdepartmental dashboard: https://app.periscopedata.com/app/gitlab/1000952/Interdepartmental-Embedded-Dashboard

Start with these 8 metrics:

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
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• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR.
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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Closes #13163 (closed)