update spgwc config override key from jsonCfgFiles to cfgFiles

Change-Id: Id82e670e72cf423bd517fd496fe8ca8151d6cdd6
diff --git a/aether-in-a-box-values.yaml b/aether-in-a-box-values.yaml
index 52608ac..a7b0011 100644
--- a/aether-in-a-box-values.yaml
+++ b/aether-in-a-box-values.yaml
@@ -44,7 +44,7 @@
           #MongoDBUrl: mongodb://mongodb:27017 #works with db in omec name space
   spgwc:
     pfcp: true
-    jsonCfgFiles:
+    cfgFiles:
       cp.json:
         ip_pool_config:
           ueIpPool: