Update git submodules

* Update docs/submodules/clover from branch 'stable/fraser'
  - Merge "Added dependent python packages to Clover container" into stable/fraser
  - Added dependent python packages to Clover container

    - Added pip grpcio and argparse packages to docker build
    - Allows service (nginx/snort) client sample scripts to be
    executed using the Clover container without having to clone
    the repo

    Change-Id: Ifeda6d58a9a381cb80372255f41ad703a089ea4b
    Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>

diff --git a/docs/submodules/clover b/docs/submodules/clover
index 1d076ac..21fef12 160000 (submodule)
--- a/docs/submodules/clover
+++ b/docs/submodules/clover
@@ -1 +1 @@
-Subproject commit 1d076ac8e0d25e01cee3a7913f459625f8c46664
+Subproject commit 21fef1217615b6840b039b62bff20bbb0d885c6c