Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 0b20199a7300d3e5f7752f698dc01b75b31ca1ce
  - Merge "Protect if {volumes} or env is None"
  - Protect if {volumes} or env is None

    Change-Id: Ieedf854c0a8e3a993f22e4e6e8fc7d9e5973771c
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index fcd901a..0b20199 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit fcd901a6dbe0e3f467543eacb0ed7eff13bbe761
+Subproject commit 0b20199a7300d3e5f7752f698dc01b75b31ca1ce