Update git submodules

* Update docs/submodules/sdc.git from branch 'master'
  to c4d387d216e72911f80c1ebee91b73aba191b91b
  - Make Cassandra port configurable.

    SDC-BE & Onboarding - BE.
    Reviewer: Evgenia A & Areli F.

    Change-Id: Iaf86d647b0560764ef65d9148c85bffaf934992d
    Issue-ID: SDC-2077
    Signed-off-by: Tal Gitelman <tal.gitelman@att.com>

diff --git a/docs/submodules/sdc.git b/docs/submodules/sdc.git
index ac3aca6..c4d387d 160000 (submodule)
--- a/docs/submodules/sdc.git
+++ b/docs/submodules/sdc.git
@@ -1 +1 @@
-Subproject commit ac3aca69dbeae29c9aeca2053adc7aedbb75e149
+Subproject commit c4d387d216e72911f80c1ebee91b73aba191b91b