Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Add Functest Hunter gates

    The system under test (functest-virtual) is downgraded to Rocky.
    It allows verifying Rocky and next Stein till the split of Functest POD.

    Change-Id: Ia161b30d9a97f517e487b3dc0f751adcc9059234
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 1b3b3ed..b871786 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 1b3b3ed8bd98fe7fb94fcc4cf46e400226cdf783
+Subproject commit b8717867d835f58de44140fd33aec75f9dfb4603