fix(fetch): properly redirect non-ascii location header url

[Xvezda]

This relates to...

Rationale

The fetch function behaves differently from major web browsers(chrome, safari, firefox etc), and even CURL (with -L option).

Here is a minimal reproducible URL I made: https://non-ascii-location-header.sys.workers.dev/redirect

Worker code

export default {
	async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
		try {
			const url = new URL(request.url);
			if (url.pathname === '/redirect') {
				return new Response('', {
					status: 302,
					headers: {
						Location: '/안녕',
					},
				});
			}
			return new Response(`pathname ${url.pathname}`);
		} catch (e) {
			return new Response(`error: ${(e as Error).message}`, { status: 500 });
		}
	},
};

By accessing the address at https://non-ascii-location-header.sys.workers.dev/redirect directly
or https://non-ascii-location-header.sys.workers.dev/ first and then making a fetch request to the /redirect path using the developer tools leads to reaching https://non-ascii-location-header.sys.workers.dev/%EC%95%88%EB%85%95
which shows pathname /%EC%95%88%EB%85%95 as a result.

However, using undici fetch function does not behave in the same way.

> r = await fetch('https://non-ascii-location-header.sys.workers.dev/redirect')
... await r.text();
pathname /%C3%AC%C2%95%C2%88%C3%AB%C2%85%C2%95

This issue can also be observed at chrome web store: https://chromewebstore.google.com/detail/gbgmenmdglilmbmemagekpeaodajbeei

Welcome to Node.js v21.6.2.
Type ".help" for more information.
> await fetch('https://chromewebstore.google.com/detail/gbgmenmdglilmbmemagekpeaodajbeei')
Uncaught TypeError: fetch failed
    at node:internal/deps/undici/undici:12443:11
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async REPL1:1:33 {
  cause: Error: redirect count exceeded
      at makeNetworkError (node:internal/deps/undici/undici:5675:35)
      at httpRedirectFetch (node:internal/deps/undici/undici:10696:32)
      at httpFetch (node:internal/deps/undici/undici:10668:28)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
      at async node:internal/deps/undici/undici:10440:20
      at async mainFetch (node:internal/deps/undici/undici:10430:20)
      at async httpFetch (node:internal/deps/undici/undici:10668:22)
      at async node:internal/deps/undici/undici:10440:20
      at async mainFetch (node:internal/deps/undici/undici:10430:20)
      at async httpFetch (node:internal/deps/undici/undici:10668:22)
}

I do not have an in-depth understanding of the fetch standard, so if this PR request violates the standard in any way, please feel free to close it.

Thank you.

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