Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 66234fba17d50750d1835f269445c796cf26a296
  - Merge "Cleaned up DeleteVnfNotification"
  - Cleaned up DeleteVnfNotification
    
    Cleaned up DeleteVnfNotification according to Sonar analyses.
    Removed unnecessary code.
    
    Change-Id: If8e35d29edb85ad4905a9373f0a820b5f7f07b72
    Issue-ID: SO-1817
    Signed-off-by: Robert Bogacki <r.bogacki@samsung.com>
    
diff --git a/docs/submodules/so.git b/docs/submodules/so.git
index d5a7006..66234fb 160000
--- a/docs/submodules/so.git
+++ b/docs/submodules/so.git
@@ -1 +1 @@
-Subproject commit d5a7006356a2f22a6e247fd96be7b06f67b1b573
+Subproject commit 66234fba17d50750d1835f269445c796cf26a296