fix: silence a11y warning for inert elements

[navorite]

closes #15814

I thought about a case where the children are inside an inert parent, perhaps in this case we should skip a11y validation altogether for all the children?

Before submitting the PR, please make sure you do the following

• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
• Prefix your PR title with feat:, fix:, chore:, or docs:.
• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.
• If this PR changes code within packages/svelte/src, add a changeset (npx changeset).

Tests and linting

• Run the tests with pnpm test and lint the project with pnpm lint

[changeset-bot]

🦋 Changeset detected

Latest commit: 34c03c3

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

This PR includes changesets to release 1 package

Name	Type
svelte	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@16339

[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-svelte-16339-svelte.vercel.app/

[Rich-Harris]

thanks!

perhaps in this case we should skip a11y validation altogether for all the children?

we could... though it seems like a real edge case tbh so i'm inclined to cross that bridge when we come to it