Update git submodules

Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge changes from topics 'lab-proxy-keyserver', 'maas-override-failed-testing'

    * changes:
      [baremetal] Use upstream lab proxy for keyservers
      [MaaS] Override failed testing by default

  - [baremetal] Use upstream lab proxy for keyservers

    Proxy chainloading does not always work for keyserver requests, so:
    - mv common.infra.lab_proxy_pdf common.include.lab_proxy_pdf;
    - mv common.include.proxy common.include.maas_proxy;
    - include lab_proxy_pdf after each maas_proxy, so if upstream_proxy
      is defined, it will override the MaaS proxy;

    JIRA: FUEL-317

    Change-Id: I63749be0d350ea73ea2cf6e629710766b14ecb73
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
  - [MaaS] Override failed testing by default

    Some nodes fail automatic testing done by MaaS during commissioning,
    although running the testing suites one more time manually works.
    For now, just override all 'failed testing' nodes unconditionally.

    JIRA: FUEL-333

    Change-Id: I13d3ee3d82550524480aa53aa8752ab90aa940cd
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>