Small tweaks to readme

[brittneypostma]

Added some more context around edge functions and examples to the readme for adapter-netlify.

Please don't delete this checklist! Before submitting the PR, please make sure you do the following:

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[changeset-bot]

🦋 Changeset detected

Latest commit: f1ab4b0

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

This PR includes changesets to release 2 packages

Name	Type
@sveltejs/adapter-netlify	Patch
@sveltejs/adapter-auto	Patch

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[Rich-Harris]

Thanks — can you run pnpm format? I would but for some reason the github CLI won't let me check out this branch

[Conduitry]

I've run pnpm format and pushed.

[brittneypostma]

Thank you both!