`Deno.serve` hangs on Windows

[ayame113]

With Deno.serve on Windows, the first request is answered successfully, but the second and subsequent requests never reach the server.

const abortController = new AbortController();

const timeoutId = setTimeout(() => {
  console.log("60 seconds passed and the server was killed.");
  abortController.abort();
}, 60 * 1000);
Deno.unrefTimer(timeoutId);

Deno.serve(() => new Response("hello world"), {
  async onListen() {
    const res1 = await fetch("http://localhost:9000/1"); // output: "res1:  hello world"
    console.log("res1: ", await res1.text());

    const res2 = await fetch("http://localhost:9000/2"); // this line is not executed on windows
    console.log("res2: ", await res2.text());

    abortController.abort();
  },
  signal: abortController.signal,
});

Here are the results of running the test code with GitHub Actions: (It looks like the results are different on Windows and Linux.)

# on linux - It looks like it's working correctly.

res1:  hello world
res2:  hello world

# on windows - Server does not process second request.

res1:  hello world
60 seconds passed and the server was killed.
error: Uncaught (in promise) TypeError: error sending request for url (http://localhost:9000/2): connection error: An existing connection was forcibly closed by the remote host. (os error 100[5](https://github.com/ayame113/deno-flash-test/runs/7964873496?check_suite_focus=true#step:4:6)4)
    const res2 = await fetch("http://localhost:9000/2");
                 ^
    at async mainFetch (deno:ext/fetch/2[6](https://github.com/ayame113/deno-flash-test/runs/7964873496?check_suite_focus=true#step:4:7)_fetch.js:2[8](https://github.com/ayame113/deno-flash-test/runs/7964873496?check_suite_focus=true#step:4:9)8:14)
    at async fetch (deno:ext/fetch/26_fetch.js:505:[9](https://github.com/ayame113/deno-flash-test/runs/7964873496?check_suite_focus=true#step:4:10))
    at async onListen (file:///D:/a/deno-flash-test/deno-flash-test/serve.ts:15:18)
Error: Process completed with exit code 1.

Here is the actual log: https://github.com/ayame113/deno-flash-test/actions

[ayame113]

If I specify Connection: close in the request header, it works as expected, but if Connection: keep-alive is specified, I think it hangs. Beyond that, I am not sure.😓