Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[doctor] fix test case name"
  - [doctor] fix test case name

    See, https://gerrit.opnfv.org/gerrit/#/c/33099/ .

    Change-Id: I3bf5bbeef88445512b70fc47be08ecc481c42c2a
    Signed-off-by: Ryota MIBU <r-mibu@cq.jp.nec.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 703f47a..780fc52 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 703f47ae905112518daa50b145be9d418fe4ca6d
+Subproject commit 780fc5289a39334ba2a16b42accc9c6c69245954