scheme is "OkHttp-Preemptive".

 *  **OkHttp now offers full-operation timeouts.** This sets a limit on how long the entire call may
    take and covers resolving DNS, connecting, writing the request body, server processing, and
    reading the full response body. If a call requires redirects or retries all must complete within
    one timeout period.

    protocol: Protocol,
    mockWebServer: MockWebServer,
  ) {
    setUp(protocol, mockWebServer)
    val settings = Settings()
    settings[Settings.MAX_CONCURRENT_STREAMS] = 2

    // Read & write a full request to confirm settings are accepted.
    server.enqueue(
      MockResponse.Builder()
        .settings(settings)
        .build(),
    )
    val call = client.newCall(Request(server.url("/")))

  builder: Builder,
) : Call.Factory, WebSocket.Factory {
  @get:JvmName("dispatcher")
  val dispatcher: Dispatcher = builder.dispatcher

  /**
   * Returns an immutable list of interceptors that observe the full span of each call: from before
   * the connection is established (if any) until after the response source is selected (either the
   * origin server, cache, or both).
   */
  @get:JvmName("interceptors")