fix: ignore popover elements in a11y_consider_explicit_label check

[RazinShafayet2007]

Description

Fixes incorrectly suppressing the a11y_consider_explicit_label warning when a button contains only a popover element.

Since popover elements are hidden from the accessibility tree until triggered, a button containing only a popover appears empty to screen readers. This change ensures the compiler ignores popover elements when checking for content, correctly triggering the warning.

Fixes

Fixes #17354

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[changeset-bot]

🦋 Changeset detected

Latest commit: df72d30

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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svelte	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-17367-svelte.vercel.app/

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Playground

pnpm add https://pkg.pr.new/svelte@17367