Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "leverage openstack's requirements rule"
  - leverage openstack's requirements rule

    change requirements.txt and test-requirements.txt to keep
    consistent with openstack's global-requirements.txt

    Change-Id: I0e62c88b957136438a23e85e41d775194bdc8757
    Signed-off-by: SerenaFeng <feng.xiaowei@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 29b23b5..8a65233 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 29b23b5a78b919b88545bc1afed772963a6c66d9
+Subproject commit 8a65233f2d7d326f7ac7d2c9f6c7d6f7185c260b