fix: Add Attachment endpoint to save file against automation rule (#4480)

Co-authored-by: fayazara <fayazara@gmail.com>
Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

config/routes.rb

@@ -55,6 +55,7 @@ Rails.application.routes.draw do
           resources :canned_responses, only: [:index, :create, :update, :destroy]
           resources :automation_rules, only: [:index, :create, :show, :update, :destroy] do
             post :clone
+            post :attach_file, on: :collection
           end
           resources :campaigns, only: [:index, :create, :show, :update, :destroy]