[message.rb]: use helper to distinguish between webhook responses

Adds two helper functions that encapsulate the properties of a
successful connector based webhook and a workflow based webhook.

Up to now, workflow based webhooks lead to a response where there
response code is 202 and the response body is empty.
For connector based webhooks, the status code is 200 and the response
body is set to "1".

lib/msteams_hermes/message.rb

@@ -3,6 +3,18 @@
 require "net/http"
 require "json"
 
+module MsTeamsWebhookType
+  def self.mst_workflow_webhook_response?(response)
+    response.code == "202" and response.body.empty?
+  end
+
+  def self.mst_connector_webhook_response?(response)
+    # For details see:
+    # https://learn.microsoft.com/en-us/microsoftteams/platform/webhooks-and-connectors/how-to/connectors-using?tabs=cURL%2Ctext1#send-messages-using-curl-and-powershell
+    response.code == "200" and response.body == "1"
+  end
+end
+
 module MsTeamsHermes
   ##
   # A class representing Microsoft's webhook message object
@@ -62,15 +74,11 @@ def deliver
 
         response = http.request(req)
 
-        # For details see:
-        # https://learn.microsoft.com/en-us/microsoftteams/platform/webhooks-and-connectors/how-to/connectors-using?tabs=cURL%2Ctext1#send-messages-using-curl-and-powershell
-        if not response.body.empty? and response.body != "1"
-          raise MessageBodyTooLargeError, body_json.bytesize if response.body.include? MSTEAMS_MESSAGE_413_ERROR_TOKEN
-
-          raise UnknownError, response.body
-        end
+        return response if MsTeamsWebhookType::mst_workflow_webhook_response?(response)
+        return response if MsTeamsWebhookType::mst_connector_webhook_response?(response)
 
-        response
+        raise MessageBodyTooLargeError, body_json.bytesize if response.body.include? MSTEAMS_MESSAGE_413_ERROR_TOKEN
+        raise UnknownError, response.body
       end
     end
     # rubocop:enable Metrics/AbcSize