fix(ext/web): fix promise chain leak of ReadableStream - #30871

Deno.test(async function readableStreamEmittingManyChunks() {
  const serverPort = 4594;
  const stopSignal = new AbortController();
  let count = 0;

  function startServer() {
    Deno.serve({ port: serverPort, signal: stopSignal.signal }, async (req) => {
      return new Response(
        new ReadableStream({
          pull(controller) {
            if (count < 30_000_000) {
              controller.enqueue(new Uint8Array([0]));
            } else {
              controller.close();
            }

            count += 1;
          },
        }),
      );
    });
  }

  async function startClient() {
    const response = await fetch(`http://localhost:${serverPort}`);
    const reader = response.body?.getReader();
    if (!reader) {
      throw new Error("client: failed to get reader from response");
    }

    while (true) {
      const { done } = await reader.read();
      if (done) break;
    }
  }

  startServer();
  await startClient();
  stopSignal.abort();
});