Update git submodules

* Update docs/submodules/snaps from branch 'master'
  - Enable https for Openstack in Snaps

    When running in https environment, snaps should provide two options:
    1. To support certification verify when https certification file is provided;
    2. To disable server certificate verification without cert file.

    JIRA: SNAPS-84

    Change-Id: I5a9094238db5c8017cc8b80e3353adc6e793b552
    Signed-off-by: Linda Wang <wangwulin@huawei.com>

diff --git a/docs/submodules/snaps b/docs/submodules/snaps
index 39b46e7..dbfb9c4 160000 (submodule)
--- a/docs/submodules/snaps
+++ b/docs/submodules/snaps
@@ -1 +1 @@
-Subproject commit 39b46e7e43dffff8f4abfbc142c9e28c9ce0d260
+Subproject commit dbfb9c4e94e500592a8b93f42b7b87230d0af311