fix additionalParamsNs/Vnf for the slice

Change-Id: I54906fc74ed798099815cc7a9165839039ea8eca
Signed-off-by: tierno <alfonso.tiernosepulveda@telefonica.com>
diff --git a/osm_nbi/nbi.py b/osm_nbi/nbi.py
index 0417c9e..a9e2b24 100644
--- a/osm_nbi/nbi.py
+++ b/osm_nbi/nbi.py
@@ -94,7 +94,7 @@
                 /<subscriptionId>                               5                       X
 
         /pdu/v1
-            /pdu_descriptor                                     O       O
+            /pdu_descriptors                                    O       O
                 /<id>                                           O               O       O       O
 
         /admin/v1