nixos/tests/glance: fix version check (#391745)

    machine_custom_port.wait_for_open_port(5678)

    soup = BeautifulSoup(machine_default.succeed("curl http://localhost:8080"))

    expected_version = "${config.nodes.machine_default.services.glance.package.version}"

    expected_version = "v${config.nodes.machine_default.services.glance.package.version}"

    assert any(a.text == expected_version for a in soup.select(".footer a"))

  '';