Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Increase ram for tempest tests (aarch64)"
  - Increase ram for tempest tests (aarch64)

    The following tests fail on armband because the VM cannot boot.
    tempest.api.compute.servers.test_server_actions.
    ServerActionsTestJSON.test_reboot_server_hard

    tempest.scenario.test_network_basic_ops.
    TestNetworkBasicOps.test_network_basic_ops

    tempest.scenario.test_volume_boot_pattern.
    TestVolumeBootPattern.test_volume_boot_pattern

    tempest.scenario.test_volume_boot_pattern.
    TestVolumeBootPatternV2.test_volume_boot_pattern

    The reason for the failure is that the 128 ram is insufficient for the
    image to boot. The fix consists in increasing the ram to 256

    JIRA: ARMBAND-61

    Change-Id: I5be1a44a8038b4952cca100511e8d08b7a37681c
    Signed-off-by: Cristina Pauna <cristina.pauna@enea.com>