adapter-cloudflare-workers: Configure custom wrangler.toml file name

[ghost]

Fixes: #7103

Adds the ability to use a config file other than wrangler.toml, like:

import adapter from '@sveltejs/adapter-cloudflare-workers';

export default {
  kit: {
    adapter: adapter({ config: '<your-wrangler-name>.toml' })
  }
};

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🦋 Changeset detected

Latest commit: 85e7ba5

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/adapter-cloudflare-workers	Minor

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[Rich-Harris]

thank you!

[ghost]

@Rich-Harris
Sorry about the naming convention (snake_case).
Thank you for fixing it for me.