I'm surprised that the function is async but context.rewrite() doesn't use an await. Is that because the rewrite is handed back off to another level of the Netlify stack to process?
Promises are flat, so if a async function or promise callback returns a promise the result is just a promise, not promise<promise>.
Using async for functions that do not use await is still a good idea because thrown errors are converted to rejected promises.
`return await` can be useful because it's a signal that the value is async, causes the current function to be included in the async stack trace, and completes local try/catch/finally blocks when the promise resolves
Actually `context.rewrite` returns a `Promise<Response>`. The `async` isn't necessary here, but it also doesn't particularly hurt. You can return a `Promise` from an async function no problem.
Since it's being returned it doesn't really matter whether `.rewrite()` is returning a promise or not. `return await x` is mostly equivalent to `return x` within an async function.
