Merge pull request Vonage#73 from Nexmo/tony-fix-send-mtm

Fix send MTM code snippet

Author: Tony Bedford

messages/whatsapp/send-mtm.sh

@@ -20,8 +20,7 @@ curl -X POST \
       "content":{
          "type":"template",
          "template":{
-            "namespace": "'$WHATSAPP_TEMPLATE_NAMESPACE'",
-            "name":"'$WHATSAPP_TEMPLATE_NAME'",
+            "name": "'$WHATSAPP_TEMPLATE_NAMESPACE':'$WHATSAPP_TEMPLATE_NAME'",
             "parameters":[
                {
                   "default":"Nexmo Verification"