Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 3a29c4dc1e0449fb1ce1c60015eacddaed874f05
  - Merge "Update Alpine to 3.11 in Functest jobs"
  - Update Alpine to 3.11 in Functest jobs

    Change-Id: Ic3564f8feca430bffb1e655688f9f5d219c7bec3
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 37f4c73..3a29c4d 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 37f4c730fb99b2241db6093e7d5076c8561f11e1
+Subproject commit 3a29c4dc1e0449fb1ce1c60015eacddaed874f05