Update git submodules

* Update docs/submodules/dovetail from branch 'master'
  - Fix the versions of openstack python client in Dovetail container

    1. Now the openstack python clients installed are always the latest.
    2. Fix them to certain versions according to the openstack requirements.
    3. The first version openstack requirements provided is newton.
    https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=stable/newton

    JIRA: DOVETAIL-615

    Change-Id: I107f8d3a4dbd95af3441c0ba410de37ba8128be3
    Signed-off-by: xudan <xudan16@huawei.com>

diff --git a/docs/submodules/dovetail b/docs/submodules/dovetail
index 931c730..05efb85 160000 (submodule)
--- a/docs/submodules/dovetail
+++ b/docs/submodules/dovetail
@@ -1 +1 @@
-Subproject commit 931c730ff814959c16f07405ba98ca5158c8f326
+Subproject commit 05efb85b4c2703be7145420c06aae5acb6778e2b