[test] Unflake static image test (#84535)
[flakiness
metric](https://app.datadoghq.com/ci/test/runs?query=test_level%3Atest%20%40git.repository.id%3A%22github.com%2Fvercel%2Fnext.js%22%20%40test.name%3A%22Static%20Image%20Component%20Tests%20development%20mode%20Should%20allow%20an%20image%20with%20a%20static%20src%20to%20omit%20height%20and%20width%22%20%40test.type%3A%22turbopack%22%20%40test.status%3A%22fail%22&agg_m=count&agg_m_source=base&agg_t=count¤tTab=overview&eventStack=&fromUser=false&index=citest&start=1759057503838&end=1759662303838&paused=false)
I suspect that the test `Should allow an image with a static src to omit
height and width` is frequently failing with `waiting for
locator('#basic-static') to be visible` because the image is covered by
one of the images with a `fill` prop, which are rendered later in the
page. This means that the image is not actually visible, even though it
is in the DOM. Playwright then fails to find it. However, I wasn't able
to reproduce this locally.
The fix is to wrap the `fill` images in a relatively positioned div with
a set height, so that they don't cover the other images.
**Before:**
<img width="490" height="894" alt="before"
src="https://github.com/user-attachments/assets/7632dc67-a649-42b7-8b62-a9a216632ec2"
/>
**After:**
<img width="490" height="894" alt="after"
src="https://github.com/user-attachments/assets/2d369e4d-ef08-47cc-bdc4-04ab94afcceb"
/>
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Co-authored-by: graphite-app[bot] <96075541+graphite-app[bot]@users.noreply.github.com>