Update git submodules

* Update docs/submodules/externalapi/nbi.git from branch 'master'
  to 4cc6d439284f5ca5ad09e14f6ac4186ca5b507e6
  - Merge "CCVPN (East-west Interface)"
  - CCVPN (East-west Interface)
    
    Issue-ID: EXTAPI-233
    Co-authored-by: madhuri.verma@vodafone.com
    Signed-off-by: Vodafone <onap@vodafone.com>
    Change-Id: I41edf2847605395d079241e60f2f21005c72fb2b
    
diff --git a/docs/submodules/externalapi/nbi.git b/docs/submodules/externalapi/nbi.git
index e49da59..4cc6d43 160000
--- a/docs/submodules/externalapi/nbi.git
+++ b/docs/submodules/externalapi/nbi.git
@@ -1 +1 @@
-Subproject commit e49da59b5e68847a83e269d988b43f863687cffc
+Subproject commit 4cc6d439284f5ca5ad09e14f6ac4186ca5b507e6