feat: remove esbuild step

[teemingc]

closes #12813
closes #12373
closes #13005

This PR removes the esbuild step from the Cloudflare adapter since Wrangler now bundles the worker for us when deploying from the Cloudflare dashboard or via the Wrangler CLI. #13072 (comment) A similar change has been implemented in the cloudflare workers PR

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🦋 Changeset detected

Latest commit: e5ceb45

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

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Name	Type
@sveltejs/adapter-cloudflare	Major

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[teemingc]

Not sure why but when testing with pkg.pr.new, the prepublish step isn't run for the cloudflare adapter.

[Rich-Harris]

preview: https://svelte-dev-git-preview-kit-13132-svelte.vercel.app/

this is an automated message