Start testing for oven-sh#2489

This appears to be a bug within the HTTPS (TLS?) connection code,
where it waits for some initial handshake before allowing timeouts
to interrupt the connection. I seen one of these fetches give up, even
from a native timeout.

test/regression/issue/02489.test.ts

@@ -0,0 +1,25 @@
+import { sleep, listen } from "bun";
+import { describe, expect, it } from "bun:test";
+
+describe("an https fetch to a silent TCP socket", () => {
+  const listener = listen({
+    port: 0,
+    hostname: "localhost",
+    socket: {
+      data() {},
+    },
+  });
+  it("should respond to abort signals", async () => {
+    const signal = AbortSignal.timeout(1);
+
+    // After 1ms, the signal should abort the fetch and reject its promise. (with an http URL, this behaviour is seen)
+    // As of this commit, however, the fetch will hang indefinitely.
+    // We detect this by requiring the rejection after waiting 250ms.
+    expect(() =>
+      Promise.race([
+        sleep(250),
+        fetch(`https://127.0.0.1:${listener.port}`, { signal: signal }).then(res => res.text()),
+      ]),
+    ).toThrow(new DOMException("The operation timed out."));
+  });
+});