feat: Add event subscription option to webhooks (#4540)

Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>
Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

spec/factories/webhooks.rb

@@ -3,5 +3,15 @@ FactoryBot.define do
     account_id { 1 }
     inbox_id { 1 }
     url { 'https://api.chatwoot.com' }
+    subscriptions do
+      %w[
+        conversation_status_changed
+        conversation_updated
+        conversation_created
+        message_created
+        message_updated
+        webwidget_triggered
+      ]
+    end
   end
 end