Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to f4dfa7097f1e51a276fbe7e8fb15c95fdeae261a
  - Merge "replace System.out by logger"
  - replace System.out by logger

    Fix sonar issues connected to using System.out instead of Logger:
    VnfInstantiationNotification,
    VnfmAdapterCreationNotification,
    VnfmAdapterDeletionNotification

    Change-Id: I7385cbbf41c68d752e76c6ad277aec004a3cca8a
    Issue-ID: SO-1811
    Signed-off-by: k.kazak <k.kazak@samsung.com>

diff --git a/docs/submodules/so.git b/docs/submodules/so.git
index 0502bae..f4dfa70 160000 (submodule)
--- a/docs/submodules/so.git
+++ b/docs/submodules/so.git
@@ -1 +1 @@
-Subproject commit 0502bae356e44cb381cd7ec0f72c7b2bd6429e87
+Subproject commit f4dfa7097f1e51a276fbe7e8fb15c95fdeae261a