🐛 [BUG] - PricingOptions accordions do not individually open/close with keyboard interaction

[alexislucio]

Describe the bug

Context

This is a continuation from https://github.com/github/githubuniverse.com/issues/2526 . While this part of the Universe website does not exist anymore, @rezrah confirmed that it's reproducible on Primer Brand.

Original content from issue

How to reproduce

1. Visit the "Save your seat" section on https://githubuniverse.com/.
2. Observe that each of the four ticket types under Individual/Group passes have a details/summary disclosure labeled identically as "What's included" with an <h4> element inside the summary.
3. Activate/collapse one summary
4. Notice the adjacent disclosure automatically opens/collapses.

A11y Impact

• The identical summary labels make it difficult for screen reader users and those with cognitive disabilities to differentiate which ticket's details are being revealed.
• The linked collapse/expand behavior is not standard for details/summary, potentially hurting discoverability and navigation.

Recommendation

• Update each summary to provide unique context, e.g., "What's included with general admission", "What's included with group pass", etc.
• Remove the linked collapse/expand functionality so users can open or close each details independently, as expected with native details/summary.
• Optionally, if the design requires collapsing the content, use a single control (e.g., "Hide what's included") that toggles visibility for both.
• Consider removing details/summary entirely and presenting this information as plain text for maximum clarity and accessibility.

Reproduction steps

1. Go to [Primer Brand Storybook component PricingOptions](https://stunning-chainsaw-j82glqz.pages.github.io/?path=/story/components-pricingoptions--default).
2. Using your keyboard only, navigate to any accordion.
3. Select `ENTER`.
4. All columns open.
5. Select `CLOSE`. All columns close.

Expected behavior

Selecting `ENTER` on a specific row should only open that row.

Screenshots

![DESCRIPTION](LINK.png)

Browsers

No response

OS

No response