Update git submodules

* Update docs/submodules/snaps from branch 'master'
  - Fix NoneType in create_router.py

    It lets Neutron handle str or unicode instead of returning None.
    It reverts the first proposal [1] which raises side effects [2].

    [1] https://gerrit.opnfv.org/gerrit/#/c/56171/
    [2] https://build.opnfv.org/ci/view/functest/job/functest-compass-baremetal-daily-master/126/console

    Change-Id: I1b45c7d6118321dd67343f31253f154abae73655
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/snaps b/docs/submodules/snaps
index 0e11064..9651c88 160000 (submodule)
--- a/docs/submodules/snaps
+++ b/docs/submodules/snaps
@@ -1 +1 @@
-Subproject commit 0e11064b4b5f49ec792784d9032161cbb3b8b023
+Subproject commit 9651c889f1b966dc2733daf7eabbb5e62268654d