Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[dovetail] Run mandatory and optional test cases with 2 jobs"
  - [dovetail] Run mandatory and optional test cases with 2 jobs

    JIRA: DOVETAIL-694

    Change-Id: I19928d57c14f99e5c3ed7725fbe3476096b1674c
    Signed-off-by: xudan <xudan16@huawei.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 91669b3..4cb31b2 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 91669b39a0a6023cee20578f49efe6e633738b06
+Subproject commit 4cb31b2b027b53c3eb7b5f8a8a4b230687999543