Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 5708597bc13fa29c27a8734c0102231200eaeea2
  - bugfix: missing " ' " symbol in doctor job

    Change-Id: I834b1475e2776e64cc4e52c02c61c70a1ea823ea
    Signed-off-by: dongwenjuan <dong.wenjuan@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index df3038e..5708597 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit df3038e208dc04961a6f2b7d243492f0c2388c0f
+Subproject commit 5708597bc13fa29c27a8734c0102231200eaeea2