Update git submodules

Update git submodules

* Update docs/submodules/dovetail from branch 'master'
  - Update class in container.py

    Change-Id: I4fb24f86c6d15aea5a62baaca20531b2891437ff
    Signed-off-by: xudan <xudan16@huawei.com>
  - CI verify jobs failed due to the update of tox

    The LF pod used to run the CI verify jobs have updated the version of tox.
    So the CI verify jobs failed.
    See https://build.opnfv.org/ci/view/dovetail/job/dovetail-merge-master/476/console

    Fix the python format errors
    Ignore error 'W503 line break before binary operator'.

    Change-Id: Ic2df070447bbea39c877ce7a394d733a95064bb1
    Signed-off-by: xudan <xudan16@huawei.com>