Use details elements for Engineering PIs

Why is this change being made?

On pages with a lot of PIs, we want to collapse the non-key ones and lazy load those, so the overall page loads more quickly.

Review app links:

1. https://details-elements-for-engineering-pis.about.gitlab-review.app/handbook/engineering/performance-indicators/ - should hide PI charts.
2. https://details-elements-for-engineering-pis.about.gitlab-review.app/handbook/engineering/development/performance-indicators/ - should hide PI charts.
3. https://details-elements-for-engineering-pis.about.gitlab-review.app/handbook/support/performance-indicators/ - should hide PI charts.
4. https://details-elements-for-engineering-pis.about.gitlab-review.app/handbook/people-group/people-success-performance-indicators/ - should not hide PI charts.

For #13105 (closed).

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
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added.
• Assign reviewers for this change to the correct DRI(s)
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the "Maintained by" section in on the page being edited.
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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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