[reporting connector] Implement Average Talk Time API

Reporting connector will expose a REST API for Average Talk Time.
API Spec:

1. API should expose a GET request for Average Talk Time
2. API should get time duration as input in url parameter. This time duration will be in seconds.
   1. time-bracket = currentTime - timeDurationSentInUrlParam e.g.
      1. API call will look like

         // This example url parameter specifies 1d/24h duration in seconds
         https://<fqdn>/<api-path>?timeDuration=86400
         

         time bracket will be last 24 hours at the API calling time in this example

         Example: https://<fqdn>/api/AvgTalkTime?timeDuration=86400

1. API will calculate per queue Average Talk Time in seconds from DB via a query and will respond with the following data structure

   // Reason Code: 200, Type: application/json
   [
     {
       "QueueId" : "<queue-1-id>",
       "AvgTalkTime" : "<queue-1-average-talk-time-in-seconds>",
       "TaskCount" : "<number of tasks in queue 1>"
     },
     {
       "QueueId" : "<queue-2-id>",
       "AvgTalkTime" : "<queue-2-average-talk-time-in-seconds>",
       "TaskCount" : "<number of tasks in queue 2>"
     }
   ]