Chore: Housekeeping tasks (#721)

- End point to return api version
- Move agent bot listener to sync dispatcher
- gem update

app/controllers/api_controller.rb

@@ -0,0 +1,8 @@
+class ApiController < ApplicationController
+  skip_before_action :set_current_user, only: [:index]
+  skip_before_action :check_subscription, only: [:index]
+
+  def index
+    render json: { version: Chatwoot.config[:version], timestamp: Time.now.utc.to_formatted_s(:db) }
+  end
+end