Update file test_onboarding.py

        descriptors_file=DESCRIPTOR_FILE, context_client=context_client, device_client=device_client)

    results = descriptor_loader.process()

    check_descriptor_load_results(results, descriptor_loader)

    time.sleep(4)  

    # replace: time.sleep(4)

    def wait_for_devices(ctx, expected, timeout=20.0, interval=0.5):

        deadline = time.time() + timeout

        last = -1

        while time.time() < deadline:

            n = len(ctx.ListDevices(Empty()).devices)

            if n == expected:

                return

            last = n

            time.sleep(interval)

        raise AssertionError(f"Timeout waiting for devices: expected {expected}, got {last}")

    # Wait until Context service actually shows all devices, then run validate()

    wait_for_devices(context_client, descriptor_loader.num_devices)

    descriptor_loader.validate()

    descriptor_loader.validate()

    # Verify the scenario has no services/slices