GR-API Yang Change. 

Add a leaf called 'payload' of type string in GR-API Yang schema in the param.resource-resolution-data container.

This is for storing the payload request that is sent to external microservice capabilities.

Extract from Yang:
   grouping param {
      list param {
         key "name";
         leaf name

{              type string; }

        leaf value

{              type string;          }

         container resource-resolution-data {
            list resource-key {
               key "name";
               leaf name

{                   type string;                }
               leaf value {                   type string;                }

            }
            leaf status

{                description "SUCCESS FAILED PENDING - RA returned data as capability";                type string;             }

            leaf capability-name

{                description "Resource assignment resolution Capability name";                type string;             }

            leaf payload

{                type string;             }

         }
      }
   }