implementation("com.squareup.okio:okio:1.15.0")
    ```

 *  Fix: Handle dispatcher executor shutdowns gracefully. When there aren't any threads to carry a
    call its callback now gets a `RejectedExecutionException`.
 *  Fix: Don't permanently cache responses with `Cache-Control: immutable`. We misunderstood the
    original `immutable` proposal!

    val requestBodyDelay = 250L
    val responseHeadersStartDelay = 250L
    val responseBodyStartDelay = 250L
    val responseBodyEndDelay = 250L

    // Warm up the client so the timing part of the test gets a pooled connection.
    server.enqueue(MockResponse())
    val warmUpCall =
      client.newCall(
        Request.Builder()
          .url(server.url("/"))
          .build(),
      )

    assertThat(rstStream.errorCode).isEqualTo(ErrorCode.CANCEL)
  }

  /**
   * When writing a set of headers fails due to an `IOException`, make sure the writer is left
   * in a consistent state so the next writer also gets an `IOException` also instead of
   * something worse (like an [IllegalStateException].
   *
   *
   * See https://github.com/square/okhttp/issues/1651
   */
  @Test fun socketExceptionWhileWritingHeaders() {