Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "The '{is-skip-vote}' is always 'true' for the jobs"
  - The '{is-skip-vote}' is always 'true' for the jobs

    fix it temporarily, will ask jjb team for this issue.

    Change-Id: I470f7114f74123f0419d2605837742208867753e
    Signed-off-by: dongwenjuan <dong.wenjuan@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index dc7000f..4c51978 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit dc7000ff2c74bc5e91aadd3e48a25f8d2edccd4b
+Subproject commit 4c5197806b1ce162e19854975648528b1d10e2e2