fix!: Sync with [email protected] based on (PR #194 & #200)

[pham]

Summary

• Fix missing 2nd arg for Server.respond() causing TypeError (see error dump below)
• Add prerendered files to public dir (thanks @AndrewLester)
• Add Node.js 18 support

Fixes: #194 #200

TypeError

⚠  functions: TypeError: Cannot read properties of undefined (reading 'prerendering')
    at respond (/tmp/svelte-adapter-firebase-wxGf/functions/sveltekit/index.js:31409:14)
    at Server.respond (/tmp/svelte-adapter-firebase-wxGf/functions/sveltekit/index.js:31705:12)
    at svelteKit (/tmp/svelte-adapter-firebase-wxGf/functions/sveltekit/index.js:31767:33)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async runFunction (/tmp/svelte-adapter-firebase-wxGf/node_modules/firebase-

[pham]

I ripped out the Node.js 18 check stuff from the merge (I didn't realize @jthegedus already removed them).

[pham]

Updated end-to-end test.

[jthegedus]

@pham You're a legend. You have come and saved me from the impending doom of updating this repo 🙏

[jthegedus]

Thanks so much @pham

[jthegedus]

I thought the ! would mean release-please would identify this as a breaking change and include in it's Release. Apparently chore takes precedent. Annoying! I'll try and fix this.